研究業績 国際会議

　　　　　　　　　　　　

2025

　　　　　　　　　　　　　

2024
  1. K. Maeda, T. Fujisawa, and M. Arai, “Excitation intensity dependence of photoluminescence in mid-infrared region for lattice-matched InAs/GaAsSb superlattice grown by MOVPE method,” 10th international conference on optical, optoelectronic and photonic materials and applications (ICOOPMA2024), P18, Czech Republic, June 2024.
  2. Y. Sawada, T. Fujisawa, T. Mitarai, T. Okimoto, H. Yagi, and N. Fujiwara “Compact four-channel wavelength multiplexer with two-stage mosaic-based waveguides designed by Bayesian direct binary search,” Optoelectronics and Communications Conference (OECC 2024), Paper TB4.1, Melbourne, Australia, June 30 to July 4, 2024.

　　　　　　　　　　　　　

2023以前
  1. T. Fujisawa and M. Koshiba, “Full-vector finite-element beam propagation method for three-dimensional nonlinear optical waveguides,” Topical Meeting on Integrated Photonics Research, IThH2, Vancouver, Canada, 2002.
  2. T. Fujisawa and M. Koshiba, “Time-domain beam propagation method for nonlinear optical propagation analysis and its application to photonic crystal circuits,” Topical Meeting on Integrated Photonics Research, IME5, Washington, USA, 2003.
  3. T. Fujisawa and M. Koshiba, “Finite-element method for nonlinear periodic optical waveguides and its application to photonic crystal circuits,” Topical Meeting on Integrated Photonics Research, IFE3, Sanfrancisco, USA, 2004.
  4. T. Fujisawa and M. Koshiba, “Finite-element characterization of nonlinear modal properties of photonic crystal waveguides,” 9th OptoElectronics and Communications Conference and 3th International Conference on Optical Internet (OECC/COIN 2004), 14F4-3, Yokohama, Japan, 2004.
  5. T. Fujisawa and M. Koshiba, “An analysis of photonic crystal waveguide gratings using coupled-mode theory and finite-element method,” Topical Meeting on Integrated Photonics Research, ITuB4, San Diego,　USA, 2005.
  6. T Fujisawa and M. Koshiba, “An analysis of air-hole type photonic crystal waveguide gratings using coupled-mode theory and finite-element method,” International Conference on Quantum Electronics 2005 and the Pacific Rim Conference on Lasers and Electro-Optics 2005 (IQEC/CLEO-PR 2005), CTuE3-3, Tokyo, Japan, July 2005.
  7. S.K. Varshney, K. Saitoh, T. Fujisawa, and M. Koshiba, “Design of gain-flattened highly nonlinear photonic crystal fiber Raman amplifier using a single pump: a leakage loss approach,” Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference (OFC/NFOEC), OWD4, Anaheim, USA, Mar. 2006.
  8. T. Fujisawa, M. Arai, T. Yamanaka, Y. Kondo, and H. Yasaka, “The Impact of InAlGaAs barriers on material and differential gain of quantum wells on low indium content InGaAs ternary substrates,” Twelfth Optoelectronics and Communications Conference/16th International Conference on Integrated Optics and Optical Fiber Communication (OECC/IOOC2007), 13D1-4, Yokohama, Japan, July 2007.
  9. M. Arai, T. Fujisawa, W. Kobayashi, Y. Kawaguchi, M. Yuda, T. Tadokoro, K. Kinoshita, T. Ueda, S. Yoda, and Y. Kondo, “A 1.31 mm ridge waveguide laser for 10 Gbps direct modulation on an InGaAs ternary substrate,” 20th Indium Phosphide and Related Materials Conference (IPRM 2008), ThA2.3, Versailles, France, 2008.
  10. T. Fujisawa, T. Sato, M. Mitsuhara, T. Kakitsuka, T. Yamanaka, Y. Kondo, and F. Kano, “Successful application of the 8-band k∙p framework to optical properties of highly strained In(Ga)As/InGaAs quantum wells with strong conduction-valence band coupling,” 8th International Conference on Numerical Simulation of Optoelectronic Devices (NUSOD ’08), ThA5, Nottingham, United Kingdom, Sep. 2008.
  11. M. Arai, T. Fujisawa, W. Kobayashi, K. Nakashima, M. Yuda, and Y. Kondo, ” High temperature operation of 1.26 mm ridge waveguide laser with InGaAs metamorphic buffer on GaAs substrate,” 2008 International Semiconductor Laser Conference (ISLC 2008), TuB4, Sorrento, Italy, 2008.
  12. W. Kobayashi, M. Arai, T. Yamanaka, N. Fujiwara, T. Fujisawa, M. Ishikawa, K. Tsuzuki, Y. Shibata, Y. Kondo, and F. Kano, “Extended operating temperature range of 125°C (-25°C to 100°C) of 10-Gbit/s, 1.55-mm electroabsorption modulator integrated DFB laser for 80-km SMF transmission,” Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference (OFC/NFOEC), OThT4, San Diego, USA, 2009.
  13. M. Arai, T. Tadokoro, W. Kobayashi, T. Fujisawa, K. Nakashima, M. Yuda, and Y. Kondo, “Uncooled (25-85°C) operation of 1.3-mm-range metamorphic InGaAs laser on GaAs substrates,” 21th Indium Phosphide and Related Materials Conference (IPRM 2009), WB1.5, Newport Beach, USA, 2009.
  14. W. Kobayashi, M. Arai, N. Fujiwara, T. Fujisawa, K. Tsuzuki, T. Ito, Y. Kondo, and F. Kano, “40 Gbit/s uncooled (-15°C to 80°C) operation of a 1.55-mm, InGaAlAs, electroabsorption modulated laser for very short reach applications,” 21th Indium Phosphide and Related Materials Conference (IPRM 2009), ThB1.2, Newport Beach, USA, 2009.
  15. T. Fujisawa, M. Arai, N. Fujiwara, W. Kobayashi, T. Tadokoro, K. Tsuzuki, Y. Akage, R. Iga, T. Yamanaka, and F. Kano, “First 40-km SMF transmission for 100-Gbit/s Ethernet system based on 25-Gbit/s 1.3-mm electroabsorption modulator integrated with a DFB laser module,” 35th European Conference and Exhibition on Optical Communication (ECOC 2009), 8.6.4, Vienna, Austria, 2009.
  16. T. Fujisawa, T. Yamanaka, T. Tadokoro, N. Fujiwara, M. Arai, W. Kobayashi, Y. Kawaguchi, K. Tsuzuki, and F. Kano, “Incident-power-dependent extinction ratio of electroabsorption modulator integrated with DFB lasers: Theory and experiment,” 2010 Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2010), CWG1, San Jose, USA, 2010.
  17. (Invited talk) W. Kobayashi, M. Arai, N. Fujiwara, T. Fujisawa, T. Tadokoro, K. Tsuzuki, T. Yamanaka, and F. Kano, “Wide temperature range operation of 10-/40-Gbps 1.55-mm electroabsorption modulator integrated with DFB laser,” 15th Optoelectronics and Communications Conference (OECC2010), 9D3-1, Sapporo, Japan, 2010.
  18. T. Fujisawa, S. Kanazawa, K. Takahata, Y. Kawaguchi, W. Kobayashi, N. Fujiwara, T. Tadokoro, T. Yamanaka, and F. Kano, “4×25-Gbit/s, 40-km SMF transmission based on 1.3-mm electroabsorption modulators integrated with DFB lasers for 100-Gbit/s Ethernet,” 15th Optoelectronics and Communications Conference (OECC2010), 6D1-2, Sapporo, Japan, 2010.
  19. (Invited talk) T. Fujisawa, S. Kanazawa, N. Nunoya, H. Ishii, Y. Kawaguchi, A. Ohki, N. Fujiwara, K. Takahata, R. Iga, F. Kano, and H. Oohashi, “4×25-Gbit/s, 1.3-mm, monolithically integrated light source for 100-Gbit/s Ethernet,” 36th European Conference and Exhibition on Optical Communication (ECOC 2010), Th.9.D.1, Turin, Italy, 2010.
  20. W. Kobayashi, K. Tsuzuki, T. Tadokoro, T. Fujisawa, N. Fujiwara, T. Yamanaka, and F. Kano, “Large bandwidth TO-CAN module with LCP based transmission line as serial 40 Gb/s 1.3/1.55-mm light source,” 2010 International Semiconductor Laser Conference (ISLC 2010), WA4, Kyoto, Japan, 2010.
  21. S. Kanazawa, T. Fujisawa, A. Ohki, H. Ishii, N. Nunoya, Y. Kawaguchi, N. Fujiwara, K. Takahata, R. Iga, F. Kano, and H. Oohashi, “Low-voltage operation of 100-Gbit/s EADFB laser array module,” 2010 International Semiconductor Laser Conference (ISLC 2010), TuC2, Kyoto, Japan, 2010.
  22. (Invited talk) T. Tadokoro, W. Kobayashi, T. Fujisawa, T. Yamanaka, and F. Kano, “High-speed modulation lasers for 100GbE applications,” Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference (OFC/NFOEC), OWD1, Los Angeles, USA, 2011.
  23. W. Kobayashi, T. Tadokoro, T. Fujisawa, N. Fujiwara, T. Yamanaka, and F. Kano, “40-Gbps Direct Modulation of 1.3-μm InGaAlAs DFB Laser in Compact TO-CAN Package,” Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference (OFC/NFOEC), OWD2, Los Angeles, USA, 2011.
  24. T. Fujisawa, K. Takahata, W. Kobayashi, T. Tadokoro, N. Fujiwara, S. Kanazawa, and F. Kano, “1.3-mm, 50-Gbit/s EADFB lasers for 400GbE,” Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference (OFC/NFOEC), OWD4, Los Angeles, USA, 2011.
  25. (Invited talk) T. Fujisawa, S. Kanazawa, H. Ishii, N. Nunoya, Y. Kawaguchi, A. Ohki, N. Fujiwara, K. Takahata, R. Iga, F. Kano, and H. Oohashi, “Monolithically integrated transmitter for 100GbE,” 16th Optoelectronics and Communications Conference (OECC2011), 7D1-1, Kaohsiung, Taiwan, 2011.
  26. T. Fujisawa, S. Kanazawa, K. Takahata, W. Kobayashi, T. Tadokoro, H. Ishii, and F. Kano, “Large-output-power, ultralow-driving-voltage (0.5 Vpp) operation of 1.3-mm, 4×25G, EADFB laser array for driverless 100GbE transmitter,” 37th European Conference and Exhibition on Optical Communication (ECOC 2011), Mo.1.LeSaleve.1, Geneve, Switzerland, 2011.
  27. K. Takahata, T. Fujisawa, S. Kanazawa, and F. Kano, “1.3-mm, 4×25G, EADFB laser array module for compact 100GbE transceivers,” IEEE Photonics 2011 Conference (IPC11), TuD2, Arlington, USA, 2011.
  28. S. Kanazawa, T. Fujisawa, N. Nunoya, A. Ohki, K. Takahata, H. Sanjoh, R. Iga, and H. Ishii, “Extremely small-form 100GbE transmitter optical sub-assembly for future inter data center cloud networks,” Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference (OFC/NFOEC), PDP5B.8, Los Angeles, USA, 2012.
  29. T. Fujisawa, K. Takahata, W. Kobayashi, R. Iga, and H. Ishii, “Theoretical and experimental investigations of laser characteristics of novel rear-grating structure and its application to uncooled light source,” 2012 Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2012), CM1A.4, San Jose, USA, 2012.
  30. (Invited talk) T. Fujisawa, S. Kanazawa, K. Takahata, W. Kobayashi, T. Tadokoro, R. Iga, and H. Ishii, “Ultra-high-speed electroabsorption modulator integrated lasers for 100GbE and beyond,” 17th Optoelectronics and Communications Conference (OECC2012), SC4_1011, Busan, Korea, 2012.
  31. W. Kobayashi, T. Tadokoro, T. Ito, T. Fujisawa, T. Yamanaka, Y. Shibata and M. Kohtoku, “High-Speed Operation at 50 Gb/s and 60-km SMF Transmission with 1.3-μm InGaAlAs-based DML,” 2012 International Semiconductor Laser Conference (ISLC 2012), TuB1, Santa Barbara
    , USA, 2012.
  32. K. Takahata, T. Fujisawa, A. Ohki, S. Kanazawa, T. Yamanaka, H. Sanjoh, R. Iga and H. Ishii, “Extremely Compact Transmitter Optical Sub-assembly for Next-generation 10-km 100GbE Transceivers,” 2012 International Semiconductor Laser Conference (ISLC 2012), TuB4, Santa Barbara, USA, 2012.
  33. T. Fujisawa, S. Kanazawa, K. Takahata, A. Ohki, Y. Ueda, R. Iga, H. Sanjoh, T. Yamanaka, M. Kohtoku, and H. Ishii, “Ultracompact, 160-Gbit/s transmitter optical subassembly based on 40-Gbit/s×4 monolithically integrated light source,” 38th European Conference and Exhibition on Optical Communication (ECOC 2012), We.1.E.1, Amsterdam, The Netherlands, 2012.
  34. (Invited talk) W. Kobayashi, T. Fujisawa, T. Itoh, T. Yamanaka, Y. Shibata, T. Tadokoro, and H. Sanjoh, “High-Speed directly modulated laser for applications of beyond 100GbE,” 25th Indium Phosphide and Related Materials Conference (IPRM 2013), TuD2-1, Kobe, Japan, 2013.
  35. Y Ueda, T. Fujisawa, K. Takahata, M. Kohtoku, H. Takahashi, and H. Ishii, “InP-based compact reflection-type transversal filter,” 25th Indium Phosphide and Related Materials Conference (IPRM 2013), TuD4-3, Kobe, Japan, 2013.
  36. S. Kanazawa, T. Fujisawa, K. Takahata, A. Ohki, R. Iga, and H. Ishii, “Low crosstalk and high modulation bandwidth 100GbE optical transmitter using flip-chip interconnects,” 25th Indium Phosphide and Related Materials Conference (IPRM 2013), TuD3-2, Kobe, Japan, 2013.
  37. W. Kobayashi, K. Tsuzuki, T. Fujisawa, Y. Ohiso, Y. Ogiso, T. Itoh, S. Kanazawa, T. Yamanaka, M. Kohtoku, and H. Sanjoh, “Challenge in extending operating wavelength range of 30 nm of 25.8-Gb/s, 1.3-mm, DML,” 10th Conference on Lasers and Electro-Optics Pacific Rim and 18th Optoelectronics and Communications Conference/Photonics Switching (CLEO-PR&OECC/PS2013), MK1-1, Kyoto, Japan, 2012.
  38. T. Fujisawa, S. Kanazawa, Y. Ueda, W. Kobayashi, K. Takahata, A. Ohki, T. Itoh, M. Kotoku, and H. Ishii, “4×25-Gbit/s EADFB laser array monolithically integrated with cascaded Mach-Zhender multiplexer,” 10th Conference on Lasers and Electro-Optics Pacific Rim and 18th Optoelectronics and Communications Conference/Photonics Switching (CLEO-PR&OECC/PS2013), MK1-3, Kyoto, Japan, 2012.
  39. T. Ohyama, A. Ohki, K. Takahata, T. Itoh, N. Nunoya, T. Fujisawa, R. Iga, and H. Sanjo, “Compact 100GbE transmitter optical sub-assembly using polarization beam combiner,” 10th Conference on Lasers and Electro-Optics Pacific Rim and 18th Optoelectronics and Communications Conference/Photonics Switching (CLEO-PR&OECC/PS2013), MK1-4, Kyoto, Japan, 2012.
  40. Y. Ueda, T. Fujisawa, S. Kanazawa, W. Kobayashi, K. Takahata, and H. Ishii, “Very-low-voltage operation of Mach-Zhender interferometer-type electroabsorption modulator,” 39th European Conference and Exhibition on Optical Communication (ECOC 2013), We.1.B.2, London, United Kingdom, 2013.
  41. W. Kobayashi, M. Arai, T. Fujisawa, Y. Shibata, T. Sato, T. Itoh, K. Hasebe, T. Yamanaka, and H. Sanjoh, “Chirp and intensity compensation using a 40-Gb/s short cavity SOA integrated EADFB laser with low power consumption,” 40th European Conference and Exhibition on Optical Communication (ECOC 2014), Mo.4.4.5, Cannes, France, 2014.
  42. Y. Ueda, T. Fujisawa, S. Kanazawa, W. Kobayashi, K. Takahata, H. Sanjoh, and H. Ishii, “Successful demonstration of low-voltage (1 Vpp) MZI-type EAM-integrated DFB laser for 25.8-Gbit/s 40-km transmission,” 2014 International Semiconductor Laser Conference (ISLC 2014), MD.03, Palma de Mallorca, Spain, 2014.
  43. S. Kanazawa, T. Fujisawa, K. Takahata, H. Sanjoh, R. Iga, and H. Ishii, “8×50-Gb/s simultaneous operation of EADFB laser array using flip-chip interconnection technique,” 2014 International Semiconductor Laser Conference (ISLC 2014), MD.06, Palma de Mallorca, Spain, 2014.
  44. (Invited talk) S. Kanazawa, T. Fujisawa, K. Takahata, H. Sanjoh, R. Iga, Y. Ueda, W. Kobayashi, and H. Ishii, “400-Gb/s operation of flip-chip interconnection EADFB laser array module,” Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference (OFC/NFOEC), Tu3l.1, Los Angeles, USA, 2015.
  45. T. Fujisawa, and K. Saitoh, “Microscopic analysis of quantum-confined Stark effect of group IV quantum wells for mid-infrared Si-based electroabsorption modulators,” 2015 Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2015), Stu4l.6, San Jose, USA, 2015.
  46. S. Makino, T. Fujisawa, and K. Saitoh, “A high-performance polarization converter based on Silicon modulated taper waveguide for polarization multiplexing designed by wavefront matching method,” 2015 Conference on Lasers and Electro-Optics – European Quantum Electronics Conference (CLEO-Europe 2015), CK-P.7, Munich, Germany, 2015.
  47. (Invited talk) N. Hanzawa, T. Sakamoto, K. Saitoh, T. Matsui, K. Tsujikawa, T. Fujisawa, and F. Yamamoto, “Mode multi/demultiplexing with parallel waveguide for mode division multiplexing transmission,” International Symposium on Ultrafast Photonic Technologies/International Symposium on extremely advanced transmission technology (ISUPT/EXAT 2015), W2.3, Kyoto, Japan, July 13-15, 2015.
  48. S. Kanazawa, T. Fujisawa, K. Takahata, R. Iga, H. Ishii and H. Sanjoh, “Low-crosstalk operation of 400-Gbit/s flip-chip interconnection EADFB laser array module,” International Nano-Optoelectronics Workshop (iNow2015), ThP15, Tokyo, 2015.
  49. T. Fujisawa, and K. Saitoh, “A principal mode analysis of strongly-coupled 3-core fibres,” 41th European Conference and Exhibition on Optical Communication (ECOC 2015), We.1.4.6, Valencia, Spain, 2015.
  50. N. Hanzawa, K. Saitoh, T. Sakamoto, T. Matsui, K. Tsujikawa, T. Fujisawa,, Y. Ishizaka, and F. Yamamoto, “Demonstration of PLC-based six-mode multiplexer for mode division multiplexing transmission,” 41th European Conference and Exhibition on Optical Communication (ECOC 2015), P.2.6, Valencia, Spain, 2015.
  51. Y. Tobita, T. Fujisawa, K. Saitoh, S. Matsuo, and K. Takenaga, “Comparison of homogeneous and heterogeneous 2LP-mode multicore fibers for high spatial multiplicity,” Frontiers in Optics/Laser Science Conference (FiO/LS 2015), FM1E.2, San Jose, USA, 2015.
  52. T. Fujisawa, and K. Saitoh, “Impulse response analysis of strongly-coupled three-core fibers,” Frontiers in Optics/Laser Science Conference (FiO/LS 2015), FM1E.3, San Jose, USA, 2015.
  53. S. Makino, T. Fujisawa, and K. Saitoh, “A high-performance polarization splitter-rotator designed by wavefront matching method,” Frontiers in Optics/Laser Science Conference (FiO/LS 2015), FM1F.4, San Jose, USA, 2015.
  54. Y. Yamashita, S. Makino, T. Fujisawa, K. Saitoh, N. Hanzawa, T. Sakamoto, T. Matsui, K. Tsujikawa, and F. Yamamoto, “Broadband LP01/LP11 PLC-based mode multi/demultiplexer designed by wavefront matching method,” Frontiers in Optics/Laser Science Conference (FiO/LS 2015), FM1F.5, San Jose, USA, 2015.
  55. T. Fujisawa, R. Tojo, S. Saitoh, S. Matsuo, and K. Saitoh, “Extremely small group delay spread six-core fiber with air-holes for mode-division-multiplexing: A principal mode analysis,” Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference (OFC/NFOEC), W2A.30, Anaheim, USA, 2016.
  56. S. Kanazawa, T. Fujisawa, K. Takahata, Y. Nakanishi, H. Yamazaki, Y. Ueda, W. Kobayashi, Y. Muramoto, H. Ishii, and H. Sanjoh, “56-Gbaud 4-PAM (112-Gbit/s) operation of flip-chip interconnection lumped-electrode EADFB laser module for equalizer-free transmission,” Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference (OFC/NFOEC), W4J.1, Anaheim, USA, 2016.
  57. S. Kanazawa, H. Yamazaki, Y. Nakanishi, T. Fujisawa, K. Takahata, Y. Ueda, W. Kobayashi, Y. Muramoto, H. Ishii, and H. Sanjoh, “Transmission of 214-Gbit/s 4-PAM signal using an ultra-broadband lumped-electrode EADFB laser module,” Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference (OFC/NFOEC), Th5B.3, Anaheim, USA, 2016.
  58. Y. Yamashita, Y. Ishizaka, N. Hanzawa, T. Fujisawa, T. Sakamoto, T. Matsui, K. Tsujikawa, F. Yamamoto, K. Nakajima, and K. Saitoh, “Excitation of LP 21b and LP02 modes with PLC-based tapered waveguide for mode-division multiplexing,” 21th Optoelectronics and Communications Conference/Photonics Switching (OECC/PS2016), TuE3, Niigata, Japan, 2016.
  59. Y. Chida, T. Fujisawa, and K. Saitoh, “Impulse response analysis of air-hole added coupled six-core fibers,” 21th Optoelectronics and Communications Conference/Photonics Switching (OECC/PS2016), MC2, Niigata, Japan, 2016.
  60. T. Fujisawa, Y. Amma, S. Matsuo, K. Aikawa, K. Saitoh and M. Koshiba, “A crosstalk analysis of heterogeneous 30-core fibre,” 42th European Conference and Exhibition on Optical Communication (ECOC 2016), Th.2.P2.SC1.7, Düsseldorf, Germany, 2016.
  61. T. Sato, S. Makino, T. Fujisawa, and K. Saitoh, “A simple design method of reflection-suppressed photonic crystal cavity with asymmetric waveguides,” 2016 IEEE Photonics Conference (IPC2016), MD1.1, Hawaii, USA, Oct. 2-6, 2016.
  62. S. Makino, T. Fujisawa, and K. Saitoh, “Ultrasmall silicon mode converters designed by wavefront matching method developed for waveguide discontinuity problem,” 2016 IEEE Photonics Conference (IPC2016), TuG3.5, Hawaii, USA, Oct. 2-6, 2016.
  63. Y. Tobita, T. Sakamoto, T. Matsui, S. Saitoh, K. Takenaga, K. Aikawa, T. Fujisawa, S. Aozasa, K. Nakajima, and K. Saitoh, “Optimum design of 4LP-mode multicore fibers with low differential mode delay for high spatial multiplicity,” 2016 IEEE Photonics Conference (IPC2016), WF2.3, Hawaii, USA, Oct. 2-6, 2016.
  64. Y. Yamashita, S. Makino, T. Fujisawa, K. Saitoh, N. Hanzawa, T. Sakamoto, T. Matsui, K. Tsujikawa, F. Yamamoto, and K. Nakajima, “A compact and low-loss PLC-based LP11a/LP11b mode rotator with curved trench structure,” 2016 IEEE Photonics Conference (IPC2016), ThA1.2, Hawaii, USA, Oct. 2-6, 2016.
  65. H. Ishihara, H. Uemura, Y. Sasaki, K. Omichi, T. Fujisawa, and K. Saitoh, “Grating inscription to few-mode multi-core fiber,” Asia Pacific Optical Sensors Conference, Th4A.13, Shanghai, China, Oct. 11-14, 2016.
  66. T. Fujisawa, Y. Yamashita, T. Sakamoto, T. Matsui, S. Makino, K. Tsujikawa, K. Nakajima, and K. Saitoh, “Scrambling-type three-mode multiplexer based on cascaded Y-branch waveguide with integrated mode rotator on PLC platform,” Optical Fiber Communication Conference (OFC 2017), Paper W1B.1, Los Angeles, USA, Mar. 19-23, 2017.
  67. T. Fujisawa, E. Taguchi, T. Sakamoto, T. Matsui, Y. Yamashita, K. Tsujikawa, K. Nakajima, and K. Saitoh, “One chip, PLC three-mode exchanger based on symmetric and asymmetric directional couplers with integrated mode rotator,” Optical Fiber Communication Conference (OFC 2017), Paper W1B.2, Los Angeles, USA, Mar. 19-23, 2017.
  68. S. Makino, M. Suga, T. Sato, T. Fujisawa, and K. Saitoh, “Ultimately low-loss and compact Si wire 90° waveguide bend composed of clothoid and normal curves for dense optical interconnect PICs,” Optical Fiber Communication Conference (OFC 2017), Paper Th3E.2, Los Angeles, USA, Mar. 19-23, 2017.
  69. T. Sato, M. Akie, M. Arai, T. Fujisawa, and K. Saitoh, “Highly efficient GeSn electroabsorprtion modulator using higher-order-mode for mid-infrared Ge-on-Si platform,” 2017 Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2017), JW2A.110, San Jose, USA, 2017.
  70. (Invited talk) T. Fujisawa, and K. Saitoh, “Material analysis of GeSn/SiGeSn quantum wells based on many-body theory,” 2017 IEEE Photonics Society Summer Topicals Meeting Series, TuA1.1, Puerto Rico, USA, 2017.
  71. (Invited talk) K. Saitoh, T. Fujisawa, and T. Sato, “Design and analysis of weakly- and strongly-coupled multicore fibers,” Advanced Photonics Congress, NeTu2B.5, New Orleans, USA, 2017.
  72. M. Akie, T. Sato, M. Arai, T. Fujisawa, and K. Saitoh, “A compact and low-loss GeSn electroabsorprtion modulator using vertical multimode interference for mid-infrared Ge-on-Si platform,” OptoElectronics and Communications Conference (OECC), P3-107, Singapore, July 31-August 4, 2017.
  73. S. Ohta, S. Makino, T. Fujisawa, T. Sakamoto, T. Matsui, K. Tsujikawa, K. Nakajima, and K. Saitoh, “A proposal of Mach-Zehnder mode multi/demultiplexer for WDM/MDM optical transmission system,” OptoElectronics and Communications Conference (OECC), P3-131, Singapore, July 31-August 4, 2017.
  74. Y. Sasaki, H. Uemura, S. Nishimoto, K. Takenaga, K. Aikawa, S. Matsuo, T. Fujisawa, and K. Saitoh, “Multicore fiber-based 5-mode multiplexer/demultiplexer,” OptoElectronics and Communications Conference (OECC), Paper 1-4B-2, Singapore, July 31-August 4, 2017.
  75. (Invited talk) K. Saitoh, T. Fujisawa, and T. Sato, “Weakly-coupled and strongly-coupled multicore fibers,” OptoElectronics and Communications Conference (OECC), Paper 2-3B-2, Singapore, July 31-August 4, 2017.
  76. T. Sato, T. Fujisawa, and K. Saitoh, “High-forward-transmission all-optical diode based on cascaded L3 photonic crystal cavities,” The 24th Congress of the International Commission for Optics (ICO-24), Th3E-03, Tokyo, Japan, Aug. 21-25, 2017.
  77. S. Ohta, T. Fujisawa, S. Makino, T. Sakamoto, T. Matsui, K. Tsujikawa, K. Nakajima, and K. Saitoh, “Mach-Zehnder mode/wavelength (de)multiplexer for WDM/MDM optical transmission,” 43th European Conference and Exhibition on Optical Communication (ECOC 2017), W.2.C.4, Gothenburg, Sweden, 2017.
  78. K. Yoshida, T. Fujisawa, T. Sato, and K. Saitoh, “Group delay spread analysis of few-mode, coupled 3-core fibres: Optimum index profile and maximum transmission distance for strong coupling regime,” 43th European Conference and Exhibition on Optical Communication (ECOC 2017), P1.SC1.8, Gothenburg, Sweden, 2017.
  79. Y. Sawada, S. Makino, T. Fujisawa, and K. Saitoh, “Development of fully three-dimensional wavefront matching method and its application to the design of ultrasmall Si mode converters,” IEEE Photonics Conference (IPC 2017), Paper WG1.1, Lake Buena Vista, USA, Oct. 1-5, 2017.
  80. M. Kudo, S. Ohta, E. Taguchi, T. Fujisawa, T. Sakamoto, T. Matsui, K. Tsujikawa, K. Nakajima, and K. Saitoh, “A Mach-Zehnder mode multi/demultiplexer based on Si/Silica hybrid PLC platform for WDM/MDM transmission,” IEEE Photonics Conference (IPC 2017), Paper ThF1.3, Lake Buena Vista, USA, Oct. 1-5, 2017.
  81. T. Fujisawa, E. Taguchi, T. Sakamoto, T. Matsui, K. Tsujikawa, K. Nakajima, and K. Saitoh, “Proposal of compact three-mode exchanger based on symmetric and asymmetric directional couplers with integrated mode rotator,” The 22nd Microoptics Conference (MOC 2017), Paper B-4, Tokyo, Japan, Nov. 19-22, 2017.
  82. S. Nakano, T. Fujisawa, T. Sato, and K. Saitoh, “Beam propagation analysis of optical activity and circular dichroism in helically twisted photonic crystal fiber,” The 22nd Microoptics Conference (MOC 2017), Paper P-16, Tokyo, Japan, Nov. 19-22, 2017.
  83. Y. Fujiwara, K. Takahashi, T. Fujisawa, K. Maeda, and M. Arai, “Sn Concentration and Surface Morphology of GeSn Layer on GaAs (311)B Substrate grown by MOVPE,” 19th International Conference on Metalorganic Vapor Phase Epitaxy, P1-39, Nara, Japan, June 2018.
  84. Y. Amma, K. Takenaga, T. Fujisawa, K. Saitoh, M. Koshiba, and K. Aikawa, “Dependence of Cladding Diameter on Inter-Core Crosstalk in Heterogeneous Multi-Core Fibers,” OptoElectronics and Communications Conference (OECC), Paper 3C2-2, Jeju, Korea, July 2-6, 2018.
  85. T. Sato, T. Fujisawa, and K. Saitoh, “Novel All-Optical Diode based on Single-Port and Four-Port Photonic Crystal Cavities,” OptoElectronics and Communications Conference (OECC), Paper 4D2-2, Jeju, Korea, July 2-6, 2018.
  86. J. Takano, T. Sato, Y. Sawada, T. Fujisawa, T. Sakamoto, T. Matsui, K. Tsujikawa, K. Nakajima, and K. Saitoh, “Proposal of Si Four-Wavelength Multiplexer using Higher-Order Mode for 100GbE,” OptoElectronics and Communications Conference (OECC), Paper 4E2-4, Jeju, Korea, July 2-6, 2018.
  87. Y. Sawada, T. Sato, T. Fujisawa, and K. Saitoh, “A Broadband Silicon Two-Mode Multiplexer Designed by Wavefront Matching Method,” OptoElectronics and Communications Conference (OECC), Paper 5E4-4, Jeju, Korea, July 2-6, 2018.
  88. (Invited talk) T. Fujisawa, T. Sakamoto, T. Matsui, K. Tsujikawa, K. Nakajima, and K. Saitoh, “PLC-based Mode Controlling Devices for Mode-Division-Multiplexing,” OptoElectronics and Communications Conference (OECC), Paper 6E1-2, Jeju, Korea, July 2-6, 2018.
  89. T. Fujisawa, M. Arai, and K. Saitoh, “Microscopic Gain Analysis of Modulation-Doped GeSn Quantum Well: Epitaxial Design toward High-Temperature Lasing,” 15th International Conference on Group IV Photonics (GFP), Paper WA3, Cancun, Mexico, Aug. 29-31, 2018.
  90. T. Sato, K. Yoshida, T. Fujisawa, T. Sakamoto, T. Matsui, K. Tsujikawa, K. Nakajima, and K. Saitoh, “Suppression of Group-Delay Spread in Coupled Two-LP-Mode Four-Core Fiber,” IEEE Photonics Conference (IPC 2018), Paper MA4.2, Reston, USA, Sept. 30-Oct. 4, 2018.
  91. J. Takano, T. Fujisawa, T. Sato, Y. Sawada, T. Sakamoto, T. Matsui, K. Tsujikawa, K. Nakajima, and K. Saitoh, “Low-loss and Fabrication-tolerant Si Four-wavelength Multiplexer Using Higher-order Mode for 100/400GbE,” Optical Fiber Communication Conference (OFC), Paper Tu2J.2, San Diego, USA, Mar. 3-7, 2019.
  92. Y. Sawada, T. Fujisawa, T. Sato, and K. Saitoh, “First Experimental Demonstration of Wavefront-matching-method-designed Silicon Mode Converters,” Optical Fiber Communication Conference (OFC), Paper W3B.4, San Diego, USA, Mar. 3-7, 2019.
  93. M. Kudo, T. Fujisawa, T. Sakamoto, T. Matsui, K. Tsujikawa, K. Nakajima, and K. Saitoh, “A Broadband Mode Divider with Arbitrary Branching Ratio Based on Wavelength-insensitive Coupler,” Optical Fiber Communication Conference (OFC), Paper Th2A.4, San Diego, USA, Mar. 3-7, 2019.
  94. Y. Yasui, K. Yoshida, T. Sato, T. Fujisawa, T. Sakamoto, T. Matsui, K. Tsujikawa, K. Nakajima, and K. Saitoh, “Simple GDS Estimation Method for Coupled Multicore Fibers with Various Core Layouts,” International Symposium on Extremely Advanced Transmission Technologies (EXAT2019), Paper P-19, Ise, Japan, May 29-31, 2019.
  95. Y. Amma, K. Takenaga, T. Fujisawa, K. Saitoh, M. Koshiba, and K. Aikawa, “Behavior of inter-core crosstalk against disturbance in heterogeneous multi-core fibers,” International Symposium on Extremely Advanced Transmission Technologies (EXAT2019), Paper P-, Ise, Japan, May 29-31, 2019.
  96. (Invited talk) T. Fujisawa, M. Arai, and K. Saitoh, “Epitaxial design of GeSn quantum wells for optoelectronic applications,” 2019 IEEE Photonics Society Summer Topicals Meeting Series, MA4.1, Miami, USA, 2019.
  97. M. Shirata, M. Kudo, T. Fujisawa, T. Sakamoto, T. Matsui, K. Tsujikawa, K. Nakajima, and K. Saitoh, “A Design of Low MDL Scrambling-type PLC 6-mode Multiplexer,” Optoelectronics and Communications Conference (OECC 2019), Paper TuE2-1, Fukuoka, Japan, July 7-11, 2019.
  98. N. Sugawara, M. Kudo, T. Fujisawa, T. Sakamoto, T. Matsui, K. Tsujikawa, K. Nakajima, and K. Saitoh, “3-Mode PLC-Based Mode Dependent Loss Equalizer in MDM Transmission,” Optoelectronics and Communications Conference (OECC 2019), Paper TuE2-2, Fukuoka, Japan, July 7-11, 2019.
  99. T. Sato, T. Fujisawa, and K. Saitoh, “Ultra-Robust Design of Mode (De)Multiplexer Based on Asymmetrical Directional Coupler Using Wire and One-Side Rib Waveguides,” Optoelectronics and Communications Conference (OECC 2019), Paper TuE2-3, Fukuoka, Japan, July 7-11, 2019.
  100. K. Nishimura, T. Sato, T. Fujisawa, Y. Amma, K. Takenaga, K. Aikawa, and K. Saitoh, “Cladding Diameter Dependence of Inter-Core Crosstalk in Heterogeneous Multicore Fibers,” Optoelectronics and Communications Conference (OECC 2019), Paper ThG3-2, Fukuoka, Japan, July 7-11, 2019.
  101. Y. Sawada, T. Fujisawa, and K. Saitoh, “Fabrication of Ultrasmall Silicon Waveguide Lenses Designed by Wavefront-Matching Method,” 16th International Conference on Group IV Photonics (GFP), Paper WP5, Singapore, Aug. 28-30, 2019.
  102. (Invited talk) M. Arai, Y. Imamura, T. Fujisawa, and K. Maeda, “MOVPE growth and evaluation of mid-infrared range superlattice,” 2019 Asia Pacific Society for Materials Research (APSMR2019), Hokkaido, Japan, 2019.
  103. M. Shirata, T. Fujisawa, T. Sakamoto, T. Matsui, K. Nakajima, and K. Saitoh, “A design of PLC-based 6-mode exchanger in mode division multiplexed transmission,” IEEE Photonics Conference (IPC 2019), Paper TuH1.4, San Antonio, USA, Sept. 30-Oct. 3, 2019.
  104. M. Shirata, T. Fujisawa, T. Sakamoto, T. Matsui, K. Nakajima, and K. Saitoh, “A Broadband PLC-type Mode Converter Designed by Wavefront Matching Method,” The 24th Microoptics Conference (MOC2019), Paper P-35, Toyama, Japan, Nov. 17-20, 2019.
  105. K. Nakamura, T. Sato, T. Fujisawa, and K. Saitoh, “Nonreciprocity Enhancement of Graphene-on-Si Waveguide using One-Dimensional Photonic Crystal,” The 24th Microoptics Conference (MOC2019), Paper P-48, Toyama, Japan, Nov. 17-20, 2019.
  106. J. Takano, T. Fujisawa, Y. Sawada, and K. Saitoh, “Low-loss silicon 2×4λ multiplexers composed of on-chip polarization-splitter-rotator and 2×2 and 2×1 Mach-Zehnder filters for 400GbE,” Optical Fiber Communication Conference (OFC), Paper M3F.4, San Diego, USA, Mar. 8-12, 2020.
  107. T. Fujisawa, T. Sakamoto, M. Miyata, T. Matsui, T. Hashimoto, R. Kasahara, K. Nakajima, and K. Saitoh, “Wavefront-matching-method-designed six-mode-exchanger based on grating-like waveguide on silica-PLC platform,” Optical Fiber Communication Conference (OFC), Paper Th1A.5, San Diego, USA, Mar. 8-12, 2020.
  108. K. Nakamura, T. Fujisawa, T. Sakamoto, T. Matsui, K. Nakajima, and K. Saitoh, “A tunable mode divider based on wavelength insensitive coupler using thermo-optic effect for gain-equalization in MDM network,” Optical Fiber Communication Conference (OFC), Paper Th2A.6, San Diego, USA, Mar. 8-12, 2020.
  109. Y. Sawada, T. Fujisawa, and K. Saitoh, “Experimental Demonstration of Broadband Silicon Mode Converter Designed by Wavefront-Matching Method,” 2020 Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2020), SM4J.6, San Jose, USA, 2020.
  110. Y. Sawada, T. Fujisawa, and K. Saitoh, “Broadband Design of Silicon Photonics Four-Mode (de)Multiplexer by Wavefront Matching Method,” 2020 Advanced Photonics Congress, Paper ITh3A.6, July 13-16, 2020.
  111. (Invited talk) K. Saitoh, T. Fujisawa, and T. Sato, “Control of group delay spread in randomly-coupled multicore fibers,” OptoElectronics and Communications Conference (OECC), T3-1-2, Taipei, Taiwan, Oct. 4-8 2020.
  112. N. Sugawara, T. Fujisawa, K. Nakamura, Y. Sawada, T. Sakamoto, T. Matsui, K. Nakajima, and K. Saitoh, “Mode Amplitude and Phase Estimation using Multimode NFP by ANN,” Optoelectronics and Communications Conference (OECC 2020), Paper T5-2-5, Taipei, Taiwan, Oct. 4-8, 2020.
  113. Y. Wang, T. Fujisawa, T. Sakamoto, T. Matsui, K. Nakajima, and K. Saitoh, “Step index 8-core fiber with 125-um cladding diameter for O-band use,” Optoelectronics and Communications Conference (OECC 2020), Paper T3-2-4, Taipei, Taiwan, Oct. 4-8, 2020.
  114. T. Fujisawa and K. Saitoh, “Ultrasmall two-mode dividers based on mosaic structure designed by direct-binary-search algorithm aided by artificial neural network,” Optoelectronics and Communications Conference (OECC 2020), Paper T5-1-3, Taipei, Taiwan, Oct. 4-8, 2020.
  115. N. Sugawara, T. Fujisawa, K. Nakamura, Y. Sawada, T. Sakamoto, T. Matsui, K. Nakajima, and K. Saitoh, “Mode amplitude and phase estimation of NFP of six-mode FMF based on artificial neural network with the help of grey-wolf-optimizer,” 46th European Conference and Exhibition on Optical Communication (ECOC 2020), Tu2A-6, online, 2020.
  116. K. Nakamura, T. Fujisawa, Y. Sawada, T. Sato, and K. Saitoh, “Ultrasmall O-band CWDM 4λ MUX based on Mosaic Structure for Dense Optical Interconnects,” 2021 Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2021), JW1A.105, San Jose, USA, 2021.
  117. Y. Sawada, T. Fujisawa, T. Sato, and K. Saitoh, “Experimental demonstration of broadband silicon 4-mode (de)multiplexer designed by wavefront-matching method,” Optical Fiber Communication Conference (OFC), Paper F2B.4, online, June. 6-10, 2021.
  118. T. Muratsubaki, T. Fujisawa, Y. Sawada, T. Sato, and K. Saitoh, “Fabrication-Tolerant Four-Mode Waveguide Crossing Based on PhC-like Subwavelength Structures at 2 μm,” Advanced Photonics Congress (APC), Paper IM2A.3, Virtual Conference, July 26-30, 2021.
  119. Y. Sawada, T. Fujisawa, T. Sato, and K. Saitoh, “Switchable Mode Converter for Four-Mode MDM System Assisted by Passive Mode Controlling Device Designed by Wavefront Matching Method,” Microoptics Conference (MOC), PO-13, online, Sept, 2021.
  120. Y. Wang, T. Fujisawa, Y. Sagae, T. Sakamoto, T. Matsui, K. Nakajima, and K. Saitoh, “125-μm Cladding Heterogeneous Step-Index Multi-core Fibers for Datacenter Networks,” The 6th International Symposium on Extremely Advanced Transmission Technologies (EXAT), Paper P-06, Virtual Conference, November 3-5, 2021.
  121. T. Sato, T. Fujisawa, T. Mitarai, T. Hiratani, T. Okimoto, T. Ishikawa, N. Kono, N. Fujiwara, H. Yagi, and K. Saitoh, “Design of Resonant-Characteristics-Monitorable Si Wavelength Filter Using Face-To-Face Loop Mirrors for Heterogeneous Integrated Tunable Lasers,” International Conference on Group IV Photonics (GFP), Paper ThB2.3, online, Dec. 8-10, 2021.
  122. T. Fujisawa, T. Mori, J. Sakamoto, Y. Yamashita, T. Sakamoto, R. Imada, R. Ima, T. Sato, K. Watanabe, R. Kasahara, T. Hashimoto, K. Nakajima, and K. Saitoh, “Silica-PLC based mode-dependent-loss equalizer for two LP mode transmission,” Optical Fiber Communication Conference (OFC), Paper M4J.4, San Diego, USA, Mar. 6-10, 2021.
  123. T. Mitarai, T. Fujisawa, T. Okimoto, N. Kono, N. Fujiwara, Y. Sawada, T. Muratsubaki, T. Sato, K. Saitoh, and H. Yagi, “Compact power splitters with mosaic-based structure designed by Bayesian direct-binary-search method,” Optoelectronics and Communications Conference (OECC 2022), Paper TuE2-4, Toyama, Japan, July 3-6, 2022.
  124. G. Ocampo, T. Sato, T. Fujisawa, Y. Amma, and K. Saitoh, “Analysis of crosstalk dependence of cladding diameter in heterogeneous multi-core fibers by considering polarization-mode coupling effects,” Optoelectronics and Communications Conference (OECC 2022), Paper TuC2-4, Toyama, Japan, July 3-6, 2022.
  125. M. Arai, K. Maeda, Y. Iwakiri, and T. Fujisawa, “Temperature Dependence of Mid-infrared Emission Process of InAs/GaSb Superlattices Grown by MOVPE,” Conference on Lasers and Electro-Optics Pacific-Rim 2022 (CLEO-PR2022), Paper CMP11A-03, Sapporo, Japan, Aug. 2022.
  126. Y. Asama, T. Fujisawa, T. Sato, T. Mori, T. Sakamoto, R. Imada, Y. Yamashita, K. Nakajima, and K. Saitoh, “Cascaded Wavefront-Matching-Method Designed 6-Mode-Exchangers for MDL Management in MDM Transmission,” Conference on Lasers and Electro-Optics Pacific-Rim 2022 (CLEO-PR2022), Paper CWP10B-05, Sapporo, Japan, Aug. 2022.
  127. T. Mori, T. Fujisawa, J. Sakamoto, Y. Yamashita, T. Sakamoto, R. Imada, R. Ima, T. Sato, K. Watanabe, R. Kasahara, T. Hashimoto, K. Saitoh, and K. Nakajima, “Variable mode-dependent-loss equalizer based on silica-PLC for two-LP-mode transmission,” 48th European Conference and Exhibition on Optical Communication (ECOC 2022), Paper Tu5.11, Sept. 2022.
  128. M. Arai, Y. Iwakiri, T. Fujisawa, and K. Maeda, “Wide wavelength range emission from InAs/GaSb type-II superlattices grown by MOVPE,” 28-th International Semiconductor Laser Conference (ISLC2022), Paper TuP-28-01, Matsue, Japan, Oct. 2022.
  129. T. Fujisawa, and K. Saitoh, “Fabrication-tolerant, 2-mode, 4λ multiplexer based on Si waveguides for beyond Tbit/s optical Ethernet,” Optical Fiber Communication Conference (OFC), Paper M1C.4, San Diego, USA, 2022.
  130. G. Ocampo, T. Sato, T. Fujisawa, M. Nakagawa, and K. Saitoh, “Relationship between Polarization Mode Dispersion and Crosstalk in Heterogeneous Multi-core Fibers with Different Cladding Diameters,” Optical Fiber Communication Conference (OFC), Paper M3B.4, San Diego, USA, 2022.
  131. T. Muratsubaki, T. Fujisawa, T. Sato, and K. Saitoh, “Compact Mode-evolution-based 2-mode 3-dB Coupler in the 2-µm Waveband Using Shortcuts to Adiabaticity,” The 7th International Symposium on Extremely Advanced Transmission Technologies (EXAT), Paper P-04, Matsue, Japan, May 17-19, 2023.
  132. H. Wang, T. Fujisawa, T. Sato, T. Mori, T. Sakamoto, Y. Yamashita, R. Imada, K. Nakajima, and K. Saitoh, “Optimization of PLC 10-mode Photonic Lantern Mode Multiplexer,” The 7th International Symposium on Extremely Advanced Transmission Technologies (EXAT), Paper P-06, Matsue, Japan, May 17-19, 2023.
  133. H. Wang, T. Fujisawa, T. Sato, and K. Saitoh, “Proposal of an ultra-compact mode multiplexer using air-hole type photonic crystal waveguides,” The 28th OptoElectronics and Communications Conference (OECC), Paper OECC2023-0317-5, Shanghai, China, July 2-6, 2023.
  134. Z. Zhao, T. Sato, T. Fujisawa, T. Iwaya, Y. Sagae, T. Sakamoto, T. Matsui, K. Nakajima, and K. Saitoh, “Design of Double-Cladding Heterogeneous 2LP-Mode 6-Core Fiber with Two-Ring Layout,” The 28th OptoElectronics and Communications Conference (OECC), Paper OECC2023-0317-7, Shanghai, China, July 2-6, 2023.
  135. T. Mitarai, T. Fujisawa, Y. Sawada, T. Okimoto, N. Kono, N. Fujiwara, T. Muratsubaki, T. Sato, K. Saitoh, and H. Yagi, “Compact passive waveguides using mosaic-based device with triangular lattice photonic crystal-like structure,” Solid State Materials and Devices (SSDM2023), Paper H-7-02, Nagoya, Japan, Sep. 5-8, 2023.
  136. H. Wang, T. Fujisawa, T. Sato, and K. Saitoh, “Proposal of 5-mode multiplexer using pillar type photonic crystal waveguides,” Microoptics Conference (MOC), Paper PO-3, Miyazaki, Japan, Sep. 24-27, 2023.
  137. K. Maeda, T. Sato, T. Fujisawa, T. Mitarai, T. Hiratani, T. Okimoto, T. Ishikawa, N. Kono, N. Fujiwara, H. Yagi, and K. Saitoh, “High Tolerant Design of Peltier-Free Si Wavelength Filter Using Mach-Zehnder Interferometer for DWDM Application,” Microoptics Conference (MOC), Paper PO-4, Miyazaki, Japan, Sep. 24-27, 2023.
  138. R. Ima, T. Fujisawa, M. Wada, T. Mori, T. Sakamoto, R. Imada, T. Sato, T. Matsui, K. Nakajima, and K. Saitoh, “Wavelength insensitive three-mode directional coupler designed by wavefront matching method for broadband mode- dependent-loss equalizer,” Microoptics Conference (MOC), Paper PO-44, Miyazaki, Japan, Sep. 24-27, 2023.
  139. S. Ochiai, T. Fujisawa, K. Nakamura, T. Sato, M. Okano, and K. Saitoh, “S+C+L Band Tapered Asymmetric Directional Coupler for Broadband Polarization Splitter-Rotator,” Microoptics Conference (MOC), Paper H-4, Miyazaki, Japan, Sep. 24-27, 2023.