Article
Nanoscience & Nanotechnology
Ruihuan Zhang, Yu He, Yong Zhang, Shaohua An, Qingming Zhu, Xingfeng Li, Yikai Su
Summary: This study demonstrates a highly efficient thermo-optic switch with extremely high power efficiency and tuning efficiency, suitable for high-speed data transmission, and it performs exceptionally well in a compact footprint.
Article
Nanoscience & Nanotechnology
Ruihuan Zhang, Yu He, Yong Zhang, Shaohua An, Qingming Zhu, Xingfeng Li, Yikai Su
Summary: This study demonstrates an on-chip power-efficient 2x2 thermo-optic switch unit using a suspended photonic crystal nanobeam structure, achieving low power consumption and high tuning efficiency for optical switching. It is suitable for high-speed data transmission and is the most power-efficient resonator-based thermo-optic switch unit reported to date.
Article
Engineering, Electrical & Electronic
Takemasa Tamanuki, Hiroyuki Ito, Toshihiko Baba
Summary: This study focuses on an optical beam scanning device utilizing photonic crystal slow-light waveguides and switch trees, operated through thermo-optic tuning at a fixed wavelength. With a custom prism lens for beam collimation, the device achieved two-dimensional scanning with a small divergence angle and low power consumption.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Optics
Fei Duan, Kai Chen, Da Chen, Yonglin Yu
Summary: The proposed 2x2 thermo-optic switch is based on MMI and MZI structures, with high switching performance and low power consumption. Compared with general thermo-optic switches, it has lower power consumption, faster response time, and superior performance.
Article
Optics
Zequn Chen, Maoliang Wei, Boshu Sun, Yang Weng, Jialing Jian, Chuyu Zhong, Chunlei Sun, Ke Si, Wei Gong, Hongtao Lin, Lan Li
Summary: This paper presents the first demonstration of flexible titanium oxide thermo-optic switches based on a Mach-Zehnder interferometer structure. The flexible switches show low insertion loss and power consumption, and exhibit excellent mechanical stability, making them promising for future flexible optoelectronic systems.
Article
Engineering, Electrical & Electronic
Humaira Zafar, Bruna Paredes, Inas Taha, Juan E. Villegas, Mahmoud Rasras, Mauro F. Pereira
Summary: This paper introduces a broadband and ultra-low crosstalk integrated silicon superlattice waveguide, enabling high-density waveguide integration. The superlattice waveguides are implemented as S-shaped adiabatic bends, which result in ultra-low crosstalks and extremely low insertion loss for the TE polarization. The measurement results show that the average insertion loss for all channels is <= 0.1 dB, and the average crosstalk values for the first and second nearest neighboring waveguides are <= -37.8 dB and <= -45.2 dB, respectively. Simulation results predict efficient broadband performance over a wavelength range of 500 nm, covering all O, E, S, C, L, and U bands. This approach is applicable to other waveguide geometries and integrated photonic platforms.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2023)
Article
Engineering, Electrical & Electronic
B. Volkan Gurses, Reza Fatemi, Aroutin Khachaturian, Ali Hajimiri
Summary: In this study, a thermo-optic phase shifter (TOPS) array architecture with independent phase control was introduced for large-scale and high-density photonic integrated circuits. Both pulse amplitude modulation (PAM) and pulse width modulation (PWM) control schemes were used. The study successfully realized compact spiral TOPS and a 288-element high-density row-column TOPS array using this architecture. Thermal crosstalk effects were analyzed, and a thermal crosstalk correction algorithm was implemented.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2022)
Article
Engineering, Electrical & Electronic
Yang Gao, Yan Xu, Songyue Liu, Xiaojian Fan, Xibin Wang, Xiaoqiang Sun, Daming Zhang
Summary: An ultra-broadband 1x2 mode switch based on cascaded Mach-Zehnder interferometer and asymmetric Y-branch is proposed, showing stable performance in converting and switching between different modes, with potential applications in wavelength-division-multiplexing & MDM complex systems.
IEEE PHOTONICS JOURNAL
(2021)
Article
Optics
Tao Chen, Zhenming Ding, Zhangqi Dang, Xinhong Jiang, Ziyang Zhang
Summary: This paper presents a function-versatile thermo-optic switch using silicon nitride waveguides embedded in polymer cladding. The device consists of an input splitter, single-mode waveguides for phase shifting, and a thermally controlled output coupler. By combining the high waveguide birefringence of silicon nitride and the thermo-optic property of the polymer, this device can achieve multiple functions such as polarization-independent path switching, beam splitting, and polarization beam splitting.
Article
Optics
Fang Zhang, Chuanlu Deng, Yi Huang, Xiaobei Zhang, Tingyun Wang
Summary: This study investigated the optimized interlayer distance for double-layer polymer optical waveguides to improve their transmission performance. Simulations were used to determine the minimal interlayer distances for waveguides with different core sizes. Experimental optimization of fabrication parameters resulted in low transmission losses and crosstalk values for the double-layer waveguides. The agreement between experimental results and simulations indicates the potential of this method for fabricating high-performance double-layer waveguides.
Article
Polymer Science
Yuqi Xie, Jiachen Han, Tian Qin, Xuyang Ge, Xihan Wu, Lu Liu, Xubin Wu, Yunji Yi
Summary: A hybrid-integrated thermo-optic switch was designed and simulated in this study, utilizing the large thermo-optical coefficient of polymer materials. By introducing the air trench structure and optimizing the heating region's structural parameters, the power consumption was significantly reduced. This device can be applied to hybrid integration fields such as array switches and ROADMs.
Article
Physics, Applied
Kohei Iino, Tomohiro Kita
Summary: In this study, we applied a differential control method and a direct-current injection-type phase shifter to a thermo-optic Mach-Zehnder interferometer optical switch, achieving fast switching. The results showed that this method enables ultrafast switching, which is significant for accelerating other thermo-optic switches.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2023)
Article
Engineering, Electrical & Electronic
Yuexin Yin, Yue Li, Mengke Yao, Xinyu Lv, Jiaqi Liang, Yuanda Wu, Daming Zhang
Summary: In this paper, a low power consumption polymer/silica hybrid thermo-optic switch based on racetrack resonator is demonstrated. By utilizing materials with high index-contrast and a simple, low-cost fabrication technology, a compact switch is successfully fabricated. The experimental results show that the switch has a high extinction ratio and low power consumption.
IEEE PHOTONICS JOURNAL
(2022)
Article
Optics
D. N. Maksimov, A. S. Kostyukov, A. E. Ershov, M. S. Molokeev, E. N. Bulgakov, V. S. Gerasimov
Summary: This study investigates thermo-optic hysteresis in a silicon structure supporting bound states in the continuum, showing that it can be obtained with low intensities of incident light at the red edge of the visible spectrum under critical coupling conditions.
Article
Engineering, Electrical & Electronic
Baizhu Lin, Shijie Sun, Xueqing Sun, Tianhang Lian, Mu Zhu, Yuanhua Che, Xibin Wang, Daming Zhang
Summary: This article proposes a dual-mode 2 x 2 thermo- optic switch based on Mach-Zehnder interferometer with symmetric directional couplers, which is experimentally demonstrated using polymer waveguides. The switch has the advantages of low power-consumption, independence on light polarization state, and can be applied in future large capacity communication systems.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2022)
Article
Multidisciplinary Sciences
Hirokazu Masai, Takahiro Ohkubo, Yasuhiro Fujii, Akitoshi Koreeda, Takayuki Yanagida, Toshiaki Ina, Kenji Kintaka
Summary: The study investigates the correlations between structural and physical properties of Ce-doped strontium borate glasses, finding that density-driven molar volume is suitable for evaluating structural data while chemical composition is better for evaluating optical and luminescent data. Borate-rich glasses exhibit stronger luminescence due to Ce3+ and internal quantum efficiency originates from the local coordination states of Ce3+ centers. Comparing numerical data of the matrix helps ensure homogeneous doping of amorphous materials by activators and determines the origin of physical properties.
SCIENTIFIC REPORTS
(2021)
Article
Engineering, Electrical & Electronic
Daiki Minemura, Shuyuan Liu, Yuya Shoji, Tetsuya Mizumoto
Summary: The proposed 3 dB polarization coupler can convert input light into two out-of-phase or in-phase TM modes, with a 3-step taper structure. By incorporating this coupler into a Mach-Zehnder interferometer, the polarization of the output light can be rotated depending on the phase difference between the two arms. This study optimized the design of the coupler and demonstrated numerically the polarization rotation in an MZI with the proposed couplers.
IEICE ELECTRONICS EXPRESS
(2021)
Article
Physics, Applied
Mario Alberto Serrano-Nunez, Yuya Shoji, Tetsuya Mizumoto
Summary: This study presents the design of an integrated transverse electric mode isolator realized by epitaxial growth of CFO film on a silicon micro-ring resonator structure, with ultra-compact sizes demonstrated numerically. Nonreciprocal phase shift can be maximized by optimizing ring cross-section and improving device performance by decreasing ring size. Optimal results are achieved by reducing ring size, simplifying device design and fabrication.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2021)
Article
Engineering, Electrical & Electronic
Mario Alberto Serrano-Nunez, Yuya Shoji, Tetsuya Mizumoto
Summary: This paper experimentally demonstrates a silicon optical isolator using a monolithically integrated cobalt ferrite film as a magneto-optical material, achieving an isolation ratio of 9.6 dB near a wavelength of 1550 nm. The device has a compact size compared to current yttrium iron garnet-based isolators due to the large Faraday rotation coefficient of cobalt ferrite. Furthermore, self-biased isolation is achieved through the strong remanence of cobalt ferrite films, eliminating the need for an external magnet. Cobalt ferrite represents a potential alternative to yttrium iron garnets for realizing practical on-chip isolation devices in silicon photonic integrated circuits due to its small footprint.
IEICE ELECTRONICS EXPRESS
(2022)
Article
Physics, Applied
Shun Yajima, Yuya Shoji
Summary: A photonic integrated circuit-based TSP solver is proposed and simulated, utilizing light's delay time to express the delay between travel points. The solver, comprising semiconductor optical amplifiers and tunable delay lines, is reconfigurable. By using a probabilistic algorithm, polynomial calculation and small footprint complexity are achieved, with a calculation time of 388 ms and footprint within 10 cm squared for a TSP of 100 points.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2022)
Article
Optics
Shuyuan Liu, Yuya Shoji, Tetsuya Mizumoto
Summary: This study demonstrates a transverse electric mode magneto-optical isolator based on an asymmetric microring resonator without additional polarization rotators in series. Cerium-substituted yttrium iron garnet is integrated with silicon-on-insulator substrates by wafer bonding to break the Lorentz reciprocity on-chip after applying a unidirectional magnetic field.
Article
Optics
Toshiya Murai, Yuya Shoji, Tetsuya Mizumoto
Summary: This study presents a scheme for light-induced thermomagnetic recording on a Si photonic platform, where lightwave coupled to a ferromagnetic thin-film magnet causes heating and a decrease in coercive force, leading to magnetization reversal. This scheme enables the realization of on-chip magneto-optical memories on the Si photonic platform without the need for complex drive systems.
Article
Engineering, Electrical & Electronic
Akihiro Noriki, Isao Tamai, Yasuhiro Ibusuki, Akio Ukita, Satoshi Suda, Koichi Takemura, Daisuke Shimura, Yosuke Onawa, Hiroki Yaegashi, Takeru Amano
Summary: In this study, we proposed a new package substrate called active optical package (AOP) substrate for co-packaged optics. We developed an optical redistribution technology on silicon photonics dies to fabricate the AOP substrate, which features a polymer waveguide and a mirror-based optical coupling between polymer and silicon waveguides. The characterized optical redistribution loss showed an average loss of approximately 4 dB and a wavelength-dependent loss of +/- 1 dB within the wavelength range of 1460-1600 nm. The study demonstrated the feasibility of low wavelength-dependent optical redistribution using the mirror-based optical coupling and polymer waveguide.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Rui Ma, Sander F. G. Reniers, Yuya Shoji, Tetsuya Mizumoto, Yuqing Jiao, Jos J. G. M. van der Tol, Kevin A. Williams
Summary: This paper demonstrates an on-chip optical circulator on the InP-membrane-on-Si (IMOS) platform. The circulator is composed of two multi-mode interferometers (MMIs), four polarization converters (PCs), and a Cerium-doped Yttrium Iron Garnet (Ce:YIG) die. The Ce:YIG die is bonded on the InP membrane via a thin bonding layer. Nonreciprocal phase shift (NRPS) is employed using a transverse magnetic field. The device functions as a 4-port optical circulator and achieves a maximum optical isolation of 27.0 dB and a minimum optical isolation of 18.6 dB for the TE mode. The proposed methods aim to improve the optical isolation bandwidth.
IEEE JOURNAL OF QUANTUM ELECTRONICS
(2023)
Article
Engineering, Electrical & Electronic
Keisuke Ozawa, Aika Taniguchi, Ryohei Ueda, Shunsuke Teranishi, Akari Watanabe, Junichi Inoue, Kenji Kintaka, Shogo Ura
Summary: A guided-mode-resonance device was designed and fabricated for narrow-band retroreflection and waveguide input coupling at 1550 nm wavelength. The device consists of a focusing grating coupler integrated in a waveguide cavity resonator constructed by a pair of distributed Bragg reflectors on a reflection substrate. The optimal length for maximum coupling was discussed both theoretically and experimentally.
IEEE PHOTONICS JOURNAL
(2023)
Article
Optics
Shun Yajima, Nobuhiko Nishiyama, Yuya Shoji
Summary: This article demonstrates a magneto-optical switch that responds to signals with a rise time of 200 ps. The switch utilizes a current-induced magnetic field to modulate the magneto-optical effect. Impedance-matching electrodes were designed to apply high-frequency current and accommodate high-speed switching. A static magnetic field generated by a permanent magnet is applied orthogonal to the current-induced fields, acting as a torque to assist in high-speed magnetization reversal.
Proceedings Paper
Optics
A. Noriki, A. Ukita, K. Takemura, S. Suda, T. Kurosu, Y. Ibusuki, I Tamai, D. Shimura, Y. Onawa, H. Yaegashi, T. Amano
Summary: In this study, a new package substrate for co-packaged optics was realized using a silicon-photonics hybrid glass-epoxy substrate with an optical redistribution layer. The transmission of 112 Gbps PAM-4 through the hybrid substrate was demonstrated with a TDECQ of less than 3.4 dB.
2022 EUROPEAN CONFERENCE ON OPTICAL COMMUNICATION (ECOC)
(2022)
Proceedings Paper
Optics
Tsuyoshi Aoki, Akihiro Noriki, Akio Ukita, Koichi Takemura, Isao Tamai, Yasuhiro Ibusuki, Taro Itatani, Satoshi Suda, Takayuki Kurosu, Fumi Nakamura, Daisuke Mizutani, Takeru Amano
Summary: A novel high-density multi-fiber passive assembly structure for connecting with polymer waveguides on a substrate is proposed. The structure includes a high-density lid ferrule holding 12 bare single mode fibers, which are attached to single mode polymer waveguides formed on an embedded high precision 12 v-grooved silicon chip as a receptacle. The prototype of the fiber array assembly shows an average connecting loss of 1.45 dB.
OPTICAL INTERCONNECTS XXII
(2022)
Proceedings Paper
Engineering, Biomedical
S. Suda, T. Kurosu, A. Noriki, I. Tamai, Y. Ibusuki, A. Ukita, K. Takemura, D. Shimura, Y. Onawa, H. Yaegashi, T. Aoki, F. Nakamura, T. Amano
Summary: Co-packaged optics technology is essential for high-capacity transmission in data centers. Polymer optical waveguides have attracted attention due to their mechanical stability, processability, and compatibility with electronic circuits. Developing an active optical package (AOP) substrate, which includes silicon photonics dies and SMF connectors on a conventional organic package substrate, allows for 3D optical wiring and high-capacity optical transmission.
ORGANIC PHOTONIC MATERIALS AND DEVICES XXIV
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Yuki Okada, Taro Itatani, Yoshinobu Okano, Takeru Amano, Satoshi Suda
Summary: A flexible polyimide fiber was demonstrated as an optical waveguide, with small transmission loss and clear mode pattern observed.
2021 IEEE CPMT SYMPOSIUM JAPAN (ICSJ)
(2021)
