Yaohui Sun, Dongyu Wang, Lihan Wang, Yue Zhou, Shilong Pan, Guohua Hu, Bin Yun, Yiping Cui
A field-programmable photonic gate array is an integrated optical chip that combines electrical control and optical processing, enabling real-time reconfiguration of the optical path through software programming. While most current optical processors rely on Mach–Zehnder interferometer (MZI)-based architectures, those based on micro-disk resonators (MDRs) offer unique characteristics, including high integration and wavelength correlation, providing new ideas for programmable photonic chip architectures. In this paper, a scalable asymmetric MZI-assisted field-programmable micro-ring array (AMZI-FPRA) processor is proposed with a cell area of only 85 × 42 µm2. This design not only has high wavelength selectivity but also possesses dual adjustable wavelengths and coupling coefficients compared with traditional MDRs. By extending the cell into a 2 × 2 AMZI-FPRA using a two-dimensional square mesh approach, it is experimentally demonstrated that different optical path topologies can be realized with a compact footprint, including bandpass bandstop filtering, optical temporal differentiation, microwave delay, wavelength-division multiplexing/demultiplexing, and optical add-drop multiplexing. Increasing the array scale will enable more versatile and high-performance microwave photonic signal processing tasks. The scheme will be a promising candidate at the present time for reconfigurable programmable photonic signal processors due to its wide reconfigurability, on-chip integration, complementary metal–oxide–semiconductor-compatibility, and low power consumption.
{"title":"Field-programmable ring array employing AMZI-assisted-MRR structure for photonic signal processor","authors":"Yaohui Sun, Dongyu Wang, Lihan Wang, Yue Zhou, Shilong Pan, Guohua Hu, Bin Yun, Yiping Cui","doi":"10.1063/5.0209603","DOIUrl":"https://doi.org/10.1063/5.0209603","url":null,"abstract":"A field-programmable photonic gate array is an integrated optical chip that combines electrical control and optical processing, enabling real-time reconfiguration of the optical path through software programming. While most current optical processors rely on Mach–Zehnder interferometer (MZI)-based architectures, those based on micro-disk resonators (MDRs) offer unique characteristics, including high integration and wavelength correlation, providing new ideas for programmable photonic chip architectures. In this paper, a scalable asymmetric MZI-assisted field-programmable micro-ring array (AMZI-FPRA) processor is proposed with a cell area of only 85 × 42 µm2. This design not only has high wavelength selectivity but also possesses dual adjustable wavelengths and coupling coefficients compared with traditional MDRs. By extending the cell into a 2 × 2 AMZI-FPRA using a two-dimensional square mesh approach, it is experimentally demonstrated that different optical path topologies can be realized with a compact footprint, including bandpass bandstop filtering, optical temporal differentiation, microwave delay, wavelength-division multiplexing/demultiplexing, and optical add-drop multiplexing. Increasing the array scale will enable more versatile and high-performance microwave photonic signal processing tasks. The scheme will be a promising candidate at the present time for reconfigurable programmable photonic signal processors due to its wide reconfigurability, on-chip integration, complementary metal–oxide–semiconductor-compatibility, and low power consumption.","PeriodicalId":504565,"journal":{"name":"APL Photonics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141405951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. W. N. Los, Mariia Sidorova, Bruno Lopez-Rodriguez, Patrick Qualm, Jin Chang, S. Steinhauer, V. Zwiller, I. Zadeh
Since their first demonstration in 2001 [Gol’tsman et al., Appl. Phys. Lett. 79, 705–707 (2001)], superconducting-nanowire single-photon detectors (SNSPDs) have witnessed two decades of great developments. SNSPDs are the detector of choice in most modern quantum optics experiments and are slowly finding their way into other photon-starved fields of optics. Until now, however, in nearly all experiments, SNSPDs were used as “binary” detectors, meaning that they could only distinguish between 0 and >=1 photons, and photon number information was lost. Recent research has demonstrated proof-of-principle photon-number resolution (PNR) SNSPDs counting 2–5 photons. The photon-number-resolving capability is highly demanded in various quantum-optics experiments, including Hong–Ou–Mandel interference, photonic quantum computing, quantum communication, and non-Gaussian quantum state preparation. In particular, PNR detectors at the wavelength range of 850–950 nm are of great interest due to the availability of high-quality semiconductor quantum dots (QDs) [Heindel et al., Adv. Opt. Photonics 15, 613–738 (2023)] and high-performance cesium-based quantum memories [Ma et al., J. Opt. 19, 043001 (2017)]. In this paper, we demonstrate NbTiN-based SNSPDs with >94% system detection efficiency, sub-11 ps timing jitter for one photon, and sub-7 ps for 2 photons. More importantly, our detectors resolve up to 7 photons using conventional cryogenic electric readout circuitry. Through theoretical analysis, we show that the PNR performance of demonstrated detectors can be further improved by enhancing the signal-to-noise ratio and bandwidth of our readout circuitry. Our results are promising for the future of optical quantum computing and quantum communication.
{"title":"High-performance photon number resolving detectors for 850–950 nm wavelength range","authors":"J. W. N. Los, Mariia Sidorova, Bruno Lopez-Rodriguez, Patrick Qualm, Jin Chang, S. Steinhauer, V. Zwiller, I. Zadeh","doi":"10.1063/5.0204340","DOIUrl":"https://doi.org/10.1063/5.0204340","url":null,"abstract":"Since their first demonstration in 2001 [Gol’tsman et al., Appl. Phys. Lett. 79, 705–707 (2001)], superconducting-nanowire single-photon detectors (SNSPDs) have witnessed two decades of great developments. SNSPDs are the detector of choice in most modern quantum optics experiments and are slowly finding their way into other photon-starved fields of optics. Until now, however, in nearly all experiments, SNSPDs were used as “binary” detectors, meaning that they could only distinguish between 0 and >=1 photons, and photon number information was lost. Recent research has demonstrated proof-of-principle photon-number resolution (PNR) SNSPDs counting 2–5 photons. The photon-number-resolving capability is highly demanded in various quantum-optics experiments, including Hong–Ou–Mandel interference, photonic quantum computing, quantum communication, and non-Gaussian quantum state preparation. In particular, PNR detectors at the wavelength range of 850–950 nm are of great interest due to the availability of high-quality semiconductor quantum dots (QDs) [Heindel et al., Adv. Opt. Photonics 15, 613–738 (2023)] and high-performance cesium-based quantum memories [Ma et al., J. Opt. 19, 043001 (2017)]. In this paper, we demonstrate NbTiN-based SNSPDs with >94% system detection efficiency, sub-11 ps timing jitter for one photon, and sub-7 ps for 2 photons. More importantly, our detectors resolve up to 7 photons using conventional cryogenic electric readout circuitry. Through theoretical analysis, we show that the PNR performance of demonstrated detectors can be further improved by enhancing the signal-to-noise ratio and bandwidth of our readout circuitry. Our results are promising for the future of optical quantum computing and quantum communication.","PeriodicalId":504565,"journal":{"name":"APL Photonics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141392970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiaotian Zhu, Chang-Xin Wang, B. E. Little, Z. Ou, S. Chu, L. Cui, Xiaoying Li
We demonstrate the generation of correlated photon pairs by using a hybrid integrated quantum photonic platform, where the dual-layer platform consists of a high-index doped silica glass (HDSG) layer to accommodate low-loss linear components and an SiN-based layer to accommodate the photon source. Leveraging the low-loss fiber coupling to the HDSG waveguide and the high nonlinearity of the SiN waveguide, we experimentally realize integrated source of photon pairs with high heralding efficiency. The directly measured photon pair rate is up to 87 KHz (corresponding to 1.74 × 10−3 pairs per pulse) when the coincidence-to-accidental ratio is greater than 10. The raw heralding efficiency can reach 18%. If the filtering loss is excluded, the heralding efficiency can further reach 29%.
{"title":"Enhanced efficiency of correlated photon pairs generation in silicon nitride with a low-loss 3D edge coupler","authors":"Xiaotian Zhu, Chang-Xin Wang, B. E. Little, Z. Ou, S. Chu, L. Cui, Xiaoying Li","doi":"10.1063/5.0198693","DOIUrl":"https://doi.org/10.1063/5.0198693","url":null,"abstract":"We demonstrate the generation of correlated photon pairs by using a hybrid integrated quantum photonic platform, where the dual-layer platform consists of a high-index doped silica glass (HDSG) layer to accommodate low-loss linear components and an SiN-based layer to accommodate the photon source. Leveraging the low-loss fiber coupling to the HDSG waveguide and the high nonlinearity of the SiN waveguide, we experimentally realize integrated source of photon pairs with high heralding efficiency. The directly measured photon pair rate is up to 87 KHz (corresponding to 1.74 × 10−3 pairs per pulse) when the coincidence-to-accidental ratio is greater than 10. The raw heralding efficiency can reach 18%. If the filtering loss is excluded, the heralding efficiency can further reach 29%.","PeriodicalId":504565,"journal":{"name":"APL Photonics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141414645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Optical resonators are widely utilized to enhance light–matter interaction by focusing electromagnetic waves into deep sub-wavelength regions. Here, we first present a metallic bowtie split ring (BSR) optical resonator as an asymmetric light coupler for a terahertz (THz) graphene photothermoelectric (PTE) detector. The giant THz field enhancement in the slit region of BSR is mediated by two types of resonances: the inductor–capacitor (LC) and the dipole resonances, which greatly increase the THz absorption, resulting in the sensitivity improvement of the THz PTE detector. In detail, the LC and dipole resonant behaviors of BSR are systematically investigated in both theoretical and experimental aspects. Compared with the dipole resonance, the LC resonance leads to stronger electric field localization and enhancement. An optimized BSR is designed and integrated with a graphene THz PTE detector, and an ultrasensitive THz PTE response is demonstrated. At room temperature and in zero-bias mode, the key detection parameters—responsivity, sensitivity (noise-equivalent power), and speed—are 138 V/W, 25 pW/Hz1/2, and 3.7 µs, respectively. Our results indicate that the LC resonance supported by BSR can introduce strong local field enhancement, which is helpful for realizing high sensitivity THz detectors.
{"title":"Ultrasensitive terahertz response mediated by split ring antenna induced giant resonant field enhancement","authors":"Jinhua Zhang, M. Cai, Xingguo Zheng, Dangdang Li, Shuxiang Ma, Xuebao Li, Jingjing Fu, Yinghao Yuan, Lin Chen, Xuguang Guo, Yiming Zhu, Songlin Zhuang","doi":"10.1063/5.0205333","DOIUrl":"https://doi.org/10.1063/5.0205333","url":null,"abstract":"Optical resonators are widely utilized to enhance light–matter interaction by focusing electromagnetic waves into deep sub-wavelength regions. Here, we first present a metallic bowtie split ring (BSR) optical resonator as an asymmetric light coupler for a terahertz (THz) graphene photothermoelectric (PTE) detector. The giant THz field enhancement in the slit region of BSR is mediated by two types of resonances: the inductor–capacitor (LC) and the dipole resonances, which greatly increase the THz absorption, resulting in the sensitivity improvement of the THz PTE detector. In detail, the LC and dipole resonant behaviors of BSR are systematically investigated in both theoretical and experimental aspects. Compared with the dipole resonance, the LC resonance leads to stronger electric field localization and enhancement. An optimized BSR is designed and integrated with a graphene THz PTE detector, and an ultrasensitive THz PTE response is demonstrated. At room temperature and in zero-bias mode, the key detection parameters—responsivity, sensitivity (noise-equivalent power), and speed—are 138 V/W, 25 pW/Hz1/2, and 3.7 µs, respectively. Our results indicate that the LC resonance supported by BSR can introduce strong local field enhancement, which is helpful for realizing high sensitivity THz detectors.","PeriodicalId":504565,"journal":{"name":"APL Photonics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141412790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Merklein, Lachlan Goulden, Max Kiewiet, Yang Liu, C. Lai, Duk-Yong Choi, Stephen J. Madden, C. G. Poulton, Benjamin J. Eggleton
Efficient and extended light storage mechanisms are pivotal in photonics, particularly in optical communications, microwave photonics, and quantum networks, as they offer a direct route to circumvent electrical conversion losses and surmount bandwidth constraints. Stimulated Brillouin Scattering (SBS) is an established method to store optical information by transferring it to the acoustic domain, but current on-chip SBS efforts have limited bandwidth or storage time due to the phonon lifetime of several nanoseconds. An alternate approach known as quasi-light storage (QLS), which involves the creation of delayed replicas of optical data pulses via SBS in conjunction with a frequency comb, has been proposed to lift the storage time constraint; however, its realization has been confined to lengthy optical fibers, constraining integration with on-chip optical elements and form factors. Here, we present an experimental demonstration of QLS on a photonic chip leveraging the large SBS gain of chalcogenide glass, achieving delays of up to 500 ns for 1 ns long signal pulses, surpassing typical Brillouin storage processes' acoustic lifetime by more than an order of magnitude and waveguide transit time by two orders of magnitude. We experimentally and numerically investigate the dynamics of on-chip QLS and reveal that the interplay between the acoustic wave that stores the optical signal and subsequent optical pump pulses leads to a reshaping of the acoustic field. Our demonstrations illustrate the potential for achieving ultra-long storage times of individual pulses by several hundred pulse widths, marking a significant stride toward advancing the field of all-optical storage and delay mechanisms.
高效、扩展的光存储机制在光子学领域，尤其是光通信、微波光子学和量子网络中至关重要，因为它们为规避电转换损耗和克服带宽限制提供了直接途径。受激布里渊散射（SBS）是一种通过将光信息转移到声学领域来存储光信息的成熟方法，但由于声子的寿命只有几纳秒，因此目前的片上 SBS 技术在带宽或存储时间方面受到限制。有人提出了另一种称为准光存储（QLS）的方法来解除存储时间的限制，这种方法是通过 SBS 与频率梳相结合来创建光数据脉冲的延迟副本；然而，这种方法的实现仅限于长光纤，限制了与片上光学元件和外形尺寸的集成。在这里，我们展示了在光子芯片上实现 QLS 的实验演示，它利用了钙化玻璃的大 SBS 增益，实现了 1 ns 长信号脉冲高达 500 ns 的延迟，比典型布里渊存储过程的声学寿命超出一个数量级，比波导传输时间超出两个数量级。我们对片上 QLS 的动态进行了实验和数值研究，发现存储光信号的声波与随后的光泵脉冲之间的相互作用导致了声场的重塑。我们的演示说明了实现数百个脉冲宽度的单个脉冲超长存储时间的潜力，标志着在推进全光存储和延迟机制领域取得了重大进展。
{"title":"On-chip quasi-light storage for long optical delays using Brillouin scattering","authors":"M. Merklein, Lachlan Goulden, Max Kiewiet, Yang Liu, C. Lai, Duk-Yong Choi, Stephen J. Madden, C. G. Poulton, Benjamin J. Eggleton","doi":"10.1063/5.0193174","DOIUrl":"https://doi.org/10.1063/5.0193174","url":null,"abstract":"Efficient and extended light storage mechanisms are pivotal in photonics, particularly in optical communications, microwave photonics, and quantum networks, as they offer a direct route to circumvent electrical conversion losses and surmount bandwidth constraints. Stimulated Brillouin Scattering (SBS) is an established method to store optical information by transferring it to the acoustic domain, but current on-chip SBS efforts have limited bandwidth or storage time due to the phonon lifetime of several nanoseconds. An alternate approach known as quasi-light storage (QLS), which involves the creation of delayed replicas of optical data pulses via SBS in conjunction with a frequency comb, has been proposed to lift the storage time constraint; however, its realization has been confined to lengthy optical fibers, constraining integration with on-chip optical elements and form factors. Here, we present an experimental demonstration of QLS on a photonic chip leveraging the large SBS gain of chalcogenide glass, achieving delays of up to 500 ns for 1 ns long signal pulses, surpassing typical Brillouin storage processes' acoustic lifetime by more than an order of magnitude and waveguide transit time by two orders of magnitude. We experimentally and numerically investigate the dynamics of on-chip QLS and reveal that the interplay between the acoustic wave that stores the optical signal and subsequent optical pump pulses leads to a reshaping of the acoustic field. Our demonstrations illustrate the potential for achieving ultra-long storage times of individual pulses by several hundred pulse widths, marking a significant stride toward advancing the field of all-optical storage and delay mechanisms.","PeriodicalId":504565,"journal":{"name":"APL Photonics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141049520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The number of photonic components integrated into the same circuit is approaching one million, but so far, this has been without the large-scale integration of active components: lasers, amplifiers, and high-speed modulators. Emerging applications in communication, sensing, and computing sectors will benefit from the functionality gained with high-density active–passive integration. Indium phosphide offers the richest possible combinations of active components, but in the past decade, their pace of integration scaling has not kept up with passive components realized in silicon. In this work, we offer a perspective for functional scaling of photonic integrated circuits with actives and passives on InP platforms, in the axes of component miniaturization, areal optimization, and wafer size scaling.
{"title":"Scaling photonic integrated circuits with InP technology: A perspective","authors":"Yi Wang, Yuqing Jiao, Kevin Williams","doi":"10.1063/5.0200861","DOIUrl":"https://doi.org/10.1063/5.0200861","url":null,"abstract":"The number of photonic components integrated into the same circuit is approaching one million, but so far, this has been without the large-scale integration of active components: lasers, amplifiers, and high-speed modulators. Emerging applications in communication, sensing, and computing sectors will benefit from the functionality gained with high-density active–passive integration. Indium phosphide offers the richest possible combinations of active components, but in the past decade, their pace of integration scaling has not kept up with passive components realized in silicon. In this work, we offer a perspective for functional scaling of photonic integrated circuits with actives and passives on InP platforms, in the axes of component miniaturization, areal optimization, and wafer size scaling.","PeriodicalId":504565,"journal":{"name":"APL Photonics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141030301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kiwon Kwon, Hyungjun Heo, Dongjin Lee, Hyeongpin Kim, Hyeong-Soon Jang, Woncheol Shin, Hyang-Tag Lim, Yong-Su Kim, Sang-Wook Han, Sangin Kim, Heedeuk Shin, Hyounghan Kwon, Hojoong Jung
Spontaneous parametric down-conversion (SPDC) has become a key method for generating entangled photon pairs. Periodically poled thin-film lithium niobate (TFLN) waveguides induce strong SPDC but require complex fabrication processes. In this work, we experimentally demonstrate efficient SPDC and second harmonic generation using modal phase matching methods. This is achieved with inverse-designed optical mode converters and low-loss optical waveguides in a single nanofabrication process. Inverse design methods provide enhanced functionalities and compact footprints for the converter. Despite the extensive achievements in inverse-designed photonic integrated circuits, the potential of inverse-designed TFLN quantum photonic devices has been seldom explored. The device shows an on-chip conversion efficiency of 3.95% W−1 cm−2 in second harmonic generation measurements and a coincidence count rate up to 21.2 kHz in SPDC experiments. This work highlights the potential of the inverse-designed TFLN photonic devices and paves the way for their applications in on-chip nonlinear or quantum optics.
{"title":"Photon-pair generation using inverse-designed thin-film lithium niobate mode converters","authors":"Kiwon Kwon, Hyungjun Heo, Dongjin Lee, Hyeongpin Kim, Hyeong-Soon Jang, Woncheol Shin, Hyang-Tag Lim, Yong-Su Kim, Sang-Wook Han, Sangin Kim, Heedeuk Shin, Hyounghan Kwon, Hojoong Jung","doi":"10.1063/5.0192026","DOIUrl":"https://doi.org/10.1063/5.0192026","url":null,"abstract":"Spontaneous parametric down-conversion (SPDC) has become a key method for generating entangled photon pairs. Periodically poled thin-film lithium niobate (TFLN) waveguides induce strong SPDC but require complex fabrication processes. In this work, we experimentally demonstrate efficient SPDC and second harmonic generation using modal phase matching methods. This is achieved with inverse-designed optical mode converters and low-loss optical waveguides in a single nanofabrication process. Inverse design methods provide enhanced functionalities and compact footprints for the converter. Despite the extensive achievements in inverse-designed photonic integrated circuits, the potential of inverse-designed TFLN quantum photonic devices has been seldom explored. The device shows an on-chip conversion efficiency of 3.95% W−1 cm−2 in second harmonic generation measurements and a coincidence count rate up to 21.2 kHz in SPDC experiments. This work highlights the potential of the inverse-designed TFLN photonic devices and paves the way for their applications in on-chip nonlinear or quantum optics.","PeriodicalId":504565,"journal":{"name":"APL Photonics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141045742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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