Journals > > Topics > Silicon Photonics
Silicon Photonics|157 Article(s)
GeSn shortwave infrared LED array prepared on GeSn nanostrips for on-chip broad-spectrum light sources
Qinxing Huang, Xiangquan Liu, Jun Zheng, Yupeng Zhu... and Buwen Cheng|Show fewer author(s)
A GeSn nanostrip grown by the rapid melting growth method has gradient Sn content along the strip, a very attractive approach for making an infrared broad-spectrum light source. In this work, by applying the Sn content distribution strategy, GeSn shortwave infrared light-emitting diodes (LEDs) arrays with a size of 3 μm×2 μm were fabricated on Si substrate, and the active layer Sn content increased from 2.1% to 5.2% to form a broadband light source. The GeSn LEDs show perfect rectifying behavior about 106 for ±1 V, and room temperature electroluminescence (EL) from the direct bandgap was achieved. The super-linear dependence between the injected current and EL intensity confirms the band-to-band radiative recombination. By utilizing Sn content gradient technology, the EL spectra of Sn gradient GeSn LED arrays can cover from 1600 to 2200 nm with a full width at half-maximum of about 340 nm. These results show a novel method for preparing broad-spectrum shortwave infrared light emitters on a Si chip. A GeSn nanostrip grown by the rapid melting growth method has gradient Sn content along the strip, a very attractive approach for making an infrared broad-spectrum light source. In this work, by applying the Sn content distribution strategy, GeSn shortwave infrared light-emitting diodes (LEDs) arrays with a size of 3 μm×2 μm were fabricated on Si substrate, and the active layer Sn content increased from 2.1% to 5.2% to form a broadband light source. The GeSn LEDs show perfect rectifying behavior about 106 for ±1 V, and room temperature electroluminescence (EL) from the direct bandgap was achieved. The super-linear dependence between the injected current and EL intensity confirms the band-to-band radiative recombination. By utilizing Sn content gradient technology, the EL spectra of Sn gradient GeSn LED arrays can cover from 1600 to 2200 nm with a full width at half-maximum of about 340 nm. These results show a novel method for preparing broad-spectrum shortwave infrared light emitters on a Si chip.
Photonics Research
- Publication Date: May. 27, 2025
- Vol. 13, Issue 6, 1572 (2025)
Fully reconfigurable silicon photonic MEMS microring resonators for DWDM
Ye Lu, Yinpeng Hu, Qian Ma, Yunzhi Liu... and Daoxin Dai|Show fewer author(s)
Reconfigurable silicon microrings have garnered significant interest for addressing challenges in artificial intelligence, the Internet of Things, and telecommunications due to their versatile capabilities. Compared to electro-optic (EO) and thermo-optic (TO) devices, emerging micro-electromechanical systems (MEMS)-based reconfigurable silicon photonic devices actuated by electrostatic forces offer near-zero static power consumption. This study proposes and implements novel designs for fully reconfigurable silicon photonic MEMS microrings for high-speed dense wavelength division multiplexing (DWDM) elastic networks. The designs include an all-pass microring with a 7 nm free spectral range (FSR) and full-FSR resonance tuning range, an add-drop microring with a 3.5 nm FSR and full-FSR tuning range, and an add-drop double-microring with a 34 nm FSR, wide-range discrete resonance tunability, and flat-top tunability. These advancements hold promise for practical applications. Reconfigurable silicon microrings have garnered significant interest for addressing challenges in artificial intelligence, the Internet of Things, and telecommunications due to their versatile capabilities. Compared to electro-optic (EO) and thermo-optic (TO) devices, emerging micro-electromechanical systems (MEMS)-based reconfigurable silicon photonic devices actuated by electrostatic forces offer near-zero static power consumption. This study proposes and implements novel designs for fully reconfigurable silicon photonic MEMS microrings for high-speed dense wavelength division multiplexing (DWDM) elastic networks. The designs include an all-pass microring with a 7 nm free spectral range (FSR) and full-FSR resonance tuning range, an add-drop microring with a 3.5 nm FSR and full-FSR tuning range, and an add-drop double-microring with a 34 nm FSR, wide-range discrete resonance tunability, and flat-top tunability. These advancements hold promise for practical applications.
Photonics Research
- Publication Date: Apr. 30, 2025
- Vol. 13, Issue 5, 1353 (2025)
Micro-transfer printing of O-band InAs/GaAs quantum-dot SOAs on silicon photonic integrated circuits|On the Cover
Yang Liu, Jing Zhang, Laurens Bogaert, Emadreza Soltanian... and Gunther Roelkens|Show fewer author(s)
Silicon photonics (SiPh) technology has become a key platform for developing photonic integrated circuits due to its CMOS compatibility and scalable manufacturing. However, integrating efficient on-chip optical sources and in-line amplifiers remains challenging due to silicon’s indirect bandgap. In this study, we developed prefabricated standardized InAs/GaAs quantum-dot (QD) active devices optimized for micro-transfer printing and successfully integrated them on SiPh integrated circuits. By transfer-printing standardized QD devices onto specific regions of the SiPh chip, we realized O-band semiconductor optical amplifiers (SOAs), distributed feedback (DFB) lasers, and widely tunable lasers (TLs). The SOAs reached an on-chip gain of 7.5 dB at 1299 nm and maintained stable performance across a wide input power range. The integrated DFB lasers achieved waveguide (WG)-coupled output powers of up to 19.7 mW, with a side-mode suppression ratio (SMSR) of 33.3 dB, and demonstrated notable robustness against optical feedback, supporting error-free data rates of 30 Gbps without additional isolators. Meanwhile, the TLs demonstrated a wavelength tuning range exceeding 35 nm, and a WG-coupled output power greater than 3 mW. The micro-transfer printing approach effectively decouples the fabrication of non-native devices from the SiPh process, allowing back-end integration of the III–V devices. Our approach offers a viable path toward fully integrated III–V/SiPh platforms capable of supporting high-speed, high-capacity communication. Silicon photonics (SiPh) technology has become a key platform for developing photonic integrated circuits due to its CMOS compatibility and scalable manufacturing. However, integrating efficient on-chip optical sources and in-line amplifiers remains challenging due to silicon’s indirect bandgap. In this study, we developed prefabricated standardized InAs/GaAs quantum-dot (QD) active devices optimized for micro-transfer printing and successfully integrated them on SiPh integrated circuits. By transfer-printing standardized QD devices onto specific regions of the SiPh chip, we realized O-band semiconductor optical amplifiers (SOAs), distributed feedback (DFB) lasers, and widely tunable lasers (TLs). The SOAs reached an on-chip gain of 7.5 dB at 1299 nm and maintained stable performance across a wide input power range. The integrated DFB lasers achieved waveguide (WG)-coupled output powers of up to 19.7 mW, with a side-mode suppression ratio (SMSR) of 33.3 dB, and demonstrated notable robustness against optical feedback, supporting error-free data rates of 30 Gbps without additional isolators. Meanwhile, the TLs demonstrated a wavelength tuning range exceeding 35 nm, and a WG-coupled output power greater than 3 mW. The micro-transfer printing approach effectively decouples the fabrication of non-native devices from the SiPh process, allowing back-end integration of the III–V devices. Our approach offers a viable path toward fully integrated III–V/SiPh platforms capable of supporting high-speed, high-capacity communication.
Photonics Research
- Publication Date: Apr. 30, 2025
- Vol. 13, Issue 5, 1341 (2025)
Dilated space-and-wavelength selective crosspoint optical switch
Ziyao Zhang, Minjia Chen, Rui Ma, Bohao Sun... and Qixiang Cheng|Show fewer author(s)
Photonic integrated switches that are both space and wavelength selective are a highly promising technology for data-intensive applications as they benefit from multi-dimensional manipulation of optical signals. However, scaling these switches normally poses stringent challenges such as increased fabrication complexity and control difficulties, due to the growing number of switching elements. In this work, we propose a new type of dilated crosspoint topology, which efficiently handles both space and wavelength selective switching, while reducing the required switching element count by an order of magnitude compared to reported designs. To the best of our knowledge, our design requires the fewest switching elements for an equivalent routing paths number and it fully cancels the first-order in-band crosstalk. We demonstrate such an ultra-compact space-and-wavelength selective switch (SWSS) at a scale of 4×4×4λ on the silicon-on-insulator (SOI) platform. Experimental results reveal that the switch achieves an insertion loss ranging from 2.3 dB to 8.6 dB and crosstalk levels in between -35.3 dB and -59.7 dB. The add-drop microring-resonators (MRRs) are equipped with micro-heaters, exhibiting a rise and fall time of 46 μs and 0.33 μs, respectively. These performance characteristics highlight the switch’s ultra-low element count and crosstalk with low insertion loss, making it a promising candidate for advanced data center applications. Photonic integrated switches that are both space and wavelength selective are a highly promising technology for data-intensive applications as they benefit from multi-dimensional manipulation of optical signals. However, scaling these switches normally poses stringent challenges such as increased fabrication complexity and control difficulties, due to the growing number of switching elements. In this work, we propose a new type of dilated crosspoint topology, which efficiently handles both space and wavelength selective switching, while reducing the required switching element count by an order of magnitude compared to reported designs. To the best of our knowledge, our design requires the fewest switching elements for an equivalent routing paths number and it fully cancels the first-order in-band crosstalk. We demonstrate such an ultra-compact space-and-wavelength selective switch (SWSS) at a scale of 4×4×4λ on the silicon-on-insulator (SOI) platform. Experimental results reveal that the switch achieves an insertion loss ranging from 2.3 dB to 8.6 dB and crosstalk levels in between -35.3 dB and -59.7 dB. The add-drop microring-resonators (MRRs) are equipped with micro-heaters, exhibiting a rise and fall time of 46 μs and 0.33 μs, respectively. These performance characteristics highlight the switch’s ultra-low element count and crosstalk with low insertion loss, making it a promising candidate for advanced data center applications.
Photonics Research
- Publication Date: Apr. 01, 2025
- Vol. 13, Issue 4, 924 (2025)
Multi-beam top-facing optical phased array enabling a 360° field of view
Jinling Guo, Weilun Zhang, Zichun Liao, Chi Zhang... and Xinliang Zhang|Show fewer author(s)
An optical phased array (OPA) featuring all-solid-state beam steering is a promising component for light detection and ranging (LiDAR). There exists an increasing demand for panoramic perception and rapid target recognition in intricate LiDAR applications, such as security systems and self-driving vehicles. However, the majority of existing OPA approaches suffer from limitations in field of view (FOV) and do not explore parallel scanning, thus restricting their potential utility. Here, we combine a two-dimensional (2D) grating with an FOV-synthetization concept to design a silicon-based top-facing OPA for realizing a wide cone-shaped 360° FOV. By utilizing four OPA units sharing the 2D grating as a single emitter, four laser beams are simultaneously emitted upwards and manipulated to scan distinct regions, demonstrating seamless beam steering within the lateral 360° range. Furthermore, a frequency-modulated dissipative Kerr-soliton (DKS) microcomb is applied to the proposed multi-beam OPA, exhibiting its capability in large-scale parallel multi-target coherent detection. The comb lines are spatially dispersed with a 2D grating and separately measure distances and velocities in parallel, significantly enhancing the parallelism. The results showcase a ranging precision of 1 cm and velocimetry errors of less than 0.5 cm/s. This approach provides an alternative solution for LiDAR with an ultra-wide FOV and massively parallel multi-target detection capability. An optical phased array (OPA) featuring all-solid-state beam steering is a promising component for light detection and ranging (LiDAR). There exists an increasing demand for panoramic perception and rapid target recognition in intricate LiDAR applications, such as security systems and self-driving vehicles. However, the majority of existing OPA approaches suffer from limitations in field of view (FOV) and do not explore parallel scanning, thus restricting their potential utility. Here, we combine a two-dimensional (2D) grating with an FOV-synthetization concept to design a silicon-based top-facing OPA for realizing a wide cone-shaped 360° FOV. By utilizing four OPA units sharing the 2D grating as a single emitter, four laser beams are simultaneously emitted upwards and manipulated to scan distinct regions, demonstrating seamless beam steering within the lateral 360° range. Furthermore, a frequency-modulated dissipative Kerr-soliton (DKS) microcomb is applied to the proposed multi-beam OPA, exhibiting its capability in large-scale parallel multi-target coherent detection. The comb lines are spatially dispersed with a 2D grating and separately measure distances and velocities in parallel, significantly enhancing the parallelism. The results showcase a ranging precision of 1 cm and velocimetry errors of less than 0.5 cm/s. This approach provides an alternative solution for LiDAR with an ultra-wide FOV and massively parallel multi-target detection capability.
Photonics Research
- Publication Date: Apr. 01, 2025
- Vol. 13, Issue 4, 889 (2025)
High-efficiency tunable lasers hybrid-integrated with silicon photonics at 2.0 μ m
Yuxuan Xie, Corey A. McDonald, Theodore J. Morin, Zhican Zhou... and Yating Wan|Show fewer author(s)
We present hybrid tunable lasers at 2.0-μm wavelength, seamlessly integrated within silicon photonic circuits for advanced biomedical applications. Leveraging III/V semiconductor materials for gain and silicon ring resonators for tuning, the laser achieves a tuning range of 25 nm, precise adjustments below 0.1 nm, and a side-mode suppression ratio of 40 dB. This advancement contributes to the progress in photonic integrated circuits beyond the telecommunication wavelength range, offering scalable and cost-effective solutions for enhanced spectroscopic systems within the 2.0-μm wavelength range. We present hybrid tunable lasers at 2.0-μm wavelength, seamlessly integrated within silicon photonic circuits for advanced biomedical applications. Leveraging III/V semiconductor materials for gain and silicon ring resonators for tuning, the laser achieves a tuning range of 25 nm, precise adjustments below 0.1 nm, and a side-mode suppression ratio of 40 dB. This advancement contributes to the progress in photonic integrated circuits beyond the telecommunication wavelength range, offering scalable and cost-effective solutions for enhanced spectroscopic systems within the 2.0-μm wavelength range.
Photonics Research
- Publication Date: Feb. 28, 2025
- Vol. 13, Issue 3, 737 (2025)
Silicon photonics convolution accelerator based on coherent chips with sub-1 pJ/MAC power consumption
Ying Zhu, Lu Xu, Xin Hua, Kailai Liu... and Shaohua Yu|Show fewer author(s)
Artificial intelligence (AI), owing to its substantial computing demands, necessitates computing hardware that offers both high speed and high power efficiency. A silicon photonic integrated circuit shows promise as a hardware solution due to its attributes, including high power efficiency, low latency, large bandwidth, and complementary metal–oxide–semiconductor (CMOS) compatibility. Here, we propose a silicon photonic convolution accelerator (SiPh-CA) and experimentally realize a prototype with sub-integrated coherent transmit–receive optical sub-assemblies (sub-IC-TROSAs). The prototype, compared to a previous IC-TROSA-based convolution accelerator, achieves almost the same performances of 1.024 TOPS/channel and 96.22% inference accuracy when it processes neural networks for image recognition, using half the numbers of the modulators and the drivers with which over 1/3 chip footprint and 37.01% power consumption are reduced. By incorporating a broadcasting scheme based on splitters and combiners, the approach can efficiently process multiple convolutions in parallel, achieving several tera operations per second. This scalability feature allows the SiPh-CA to process complex AI and high-performance computing tasks. Artificial intelligence (AI), owing to its substantial computing demands, necessitates computing hardware that offers both high speed and high power efficiency. A silicon photonic integrated circuit shows promise as a hardware solution due to its attributes, including high power efficiency, low latency, large bandwidth, and complementary metal–oxide–semiconductor (CMOS) compatibility. Here, we propose a silicon photonic convolution accelerator (SiPh-CA) and experimentally realize a prototype with sub-integrated coherent transmit–receive optical sub-assemblies (sub-IC-TROSAs). The prototype, compared to a previous IC-TROSA-based convolution accelerator, achieves almost the same performances of 1.024 TOPS/channel and 96.22% inference accuracy when it processes neural networks for image recognition, using half the numbers of the modulators and the drivers with which over 1/3 chip footprint and 37.01% power consumption are reduced. By incorporating a broadcasting scheme based on splitters and combiners, the approach can efficiently process multiple convolutions in parallel, achieving several tera operations per second. This scalability feature allows the SiPh-CA to process complex AI and high-performance computing tasks.
Photonics Research
- Publication Date: Jan. 31, 2025
- Vol. 13, Issue 2, 497 (2025)
All-optically linearized silicon modulator with ultrahigh SFDR of 131 dB · Hz6/7
Qiang Zhang, Qikai Huang, Penghui Xia, Yan Li... and Hui Yu|Show fewer author(s)
Integrated high-linearity modulators are crucial for high dynamic-range microwave photonic (MWP) systems. Conventional linearization schemes usually involve the fine tuning of radio-frequency (RF) power distribution, which is rather inconvenient for practical applications and can hardly be implemented on the integrated photonics chip. In this paper, we propose an elegant scheme to linearize a silicon-based modulator in which the active tuning of RF power is eliminated. The device consists of two carrier-depletion-based Mach–Zehnder modulators (MZMs), which are connected in series by a 1×2 thermal optical switch (OS). The OS is used to adjust the ratio between the modulation depths of the two sub-MZMs. Under a proper ratio, the complementary third-order intermodulation distortion (IMD3) of the two sub-MZMs can effectively cancel each other out. The measured spurious-free dynamic ranges for IMD3 are 131, 127, 118, 110, and 109 dB·Hz6/7 at frequencies of 1, 10, 20, 30, and 40 GHz, respectively, which represent the highest linearities ever reached by the integrated modulator chips on all available material platforms. Integrated high-linearity modulators are crucial for high dynamic-range microwave photonic (MWP) systems. Conventional linearization schemes usually involve the fine tuning of radio-frequency (RF) power distribution, which is rather inconvenient for practical applications and can hardly be implemented on the integrated photonics chip. In this paper, we propose an elegant scheme to linearize a silicon-based modulator in which the active tuning of RF power is eliminated. The device consists of two carrier-depletion-based Mach–Zehnder modulators (MZMs), which are connected in series by a 1×2 thermal optical switch (OS). The OS is used to adjust the ratio between the modulation depths of the two sub-MZMs. Under a proper ratio, the complementary third-order intermodulation distortion (IMD3) of the two sub-MZMs can effectively cancel each other out. The measured spurious-free dynamic ranges for IMD3 are 131, 127, 118, 110, and 109 dB·Hz6/7 at frequencies of 1, 10, 20, 30, and 40 GHz, respectively, which represent the highest linearities ever reached by the integrated modulator chips on all available material platforms.
Photonics Research
- Publication Date: Jan. 30, 2025
- Vol. 13, Issue 2, 433 (2025)
Polarization-insensitive silicon intensity modulator with a maximum speed of 224 Gb/s
Zanyun Zhang, Beiju Huang, Qixin Wang, Zilong Chen... and Graham T. Reed|Show fewer author(s)
Polarization-insensitive optical modulators allow an external laser to be remotely interconnected by single-mode optical fibers while avoiding polarization controllers, which would be convenient and cost-effective for co-packaged optics, 5G, and future 6G applications. In this article, a polarization-insensitive silicon intensity modulator is proposed and experimentally demonstrated based on two-dimensional centrally symmetric gratings, featuring a low polarization-dependent loss of 0.15 dB in minimum and polarization insensitivity of eye diagrams. The device exhibits a low fiber-to-fiber insertion loss of 9 dB and an electro-optic (EO) bandwidth of 49.8 GHz. A modulation speed of up to 224 Gb/s is also demonstrated. Polarization-insensitive optical modulators allow an external laser to be remotely interconnected by single-mode optical fibers while avoiding polarization controllers, which would be convenient and cost-effective for co-packaged optics, 5G, and future 6G applications. In this article, a polarization-insensitive silicon intensity modulator is proposed and experimentally demonstrated based on two-dimensional centrally symmetric gratings, featuring a low polarization-dependent loss of 0.15 dB in minimum and polarization insensitivity of eye diagrams. The device exhibits a low fiber-to-fiber insertion loss of 9 dB and an electro-optic (EO) bandwidth of 49.8 GHz. A modulation speed of up to 224 Gb/s is also demonstrated.
Photonics Research
- Publication Date: Jan. 09, 2025
- Vol. 13, Issue 2, 274 (2025)
Correction of laser sweeping nonlinearities using ultralow-loss on-chip 7 m spiral resonators
Osama Terra, Warren Jin, Hussein Kotb, Joel Guo, and John E. Bowers
Swept laser interferometry is an extremely powerful solution embedded in several recent technologies such as absolute distance measurement, light detection and ranging (LiDAR), optical frequency domain reflectometry, optical coherence tomography, microresonator characterization, and gas spectroscopy. Nonlinearity in the optical frequency sweeping of tunable lasers is a fatal drawback in gaining the expected outcome from these technologies. Here, we introduce an on-chip, millimeter-scale, 7 m spiral resonator that is made of ultralow-loss Si3N4 to act as a frequency ruler for correction of the tunable lasers sweeping nonlinearities. The sharp 2 MHz frequency lines of the 8.5×107 high-quality factor resonator and the narrow-spaced 25.566 MHz frequency ticks of the 7 m spiral allow unprecedented precision for an on-chip solution to correct the laser sweeping nonlinearity. Accurate measurements of the ruler’s frequency spacing, linewidth, and temperature and wavelength sensitivities of the frequency ticks are performed here to demonstrate the quality of the frequency ruler. In addition, the spiral resonator is implemented in an frequency-modulated continuous-wave LiDAR experiment to demonstrate a potential application of the proposed on-chip frequency ruler. Swept laser interferometry is an extremely powerful solution embedded in several recent technologies such as absolute distance measurement, light detection and ranging (LiDAR), optical frequency domain reflectometry, optical coherence tomography, microresonator characterization, and gas spectroscopy. Nonlinearity in the optical frequency sweeping of tunable lasers is a fatal drawback in gaining the expected outcome from these technologies. Here, we introduce an on-chip, millimeter-scale, 7 m spiral resonator that is made of ultralow-loss Si3N4 to act as a frequency ruler for correction of the tunable lasers sweeping nonlinearities. The sharp 2 MHz frequency lines of the 8.5×107 high-quality factor resonator and the narrow-spaced 25.566 MHz frequency ticks of the 7 m spiral allow unprecedented precision for an on-chip solution to correct the laser sweeping nonlinearity. Accurate measurements of the ruler’s frequency spacing, linewidth, and temperature and wavelength sensitivities of the frequency ticks are performed here to demonstrate the quality of the frequency ruler. In addition, the spiral resonator is implemented in an frequency-modulated continuous-wave LiDAR experiment to demonstrate a potential application of the proposed on-chip frequency ruler.
Photonics Research
- Publication Date: Dec. 16, 2024
- Vol. 13, Issue 1, 40 (2025)
Topics
- <
- 1
- 2
- 3
- ...
- 16
- >
© Copyright 2018-2021 | Chinese Laser Press. All Rights Reserved 沪ICP备15018463号-20