Hanfa Song, Tyler J. Zimmerling, Bo Leng, Vien Van
Conventional topological photonic insulators typically have narrow nontrivial band gaps truncated by broad dispersive bulk bands, resulting in limited edge mode transmission bandwidths that can be exploited for potential applications. Here, we demonstrate a Floquet–Lieb topological photonic insulator with all flat bands that can support continuous edge mode transmission across multiple Floquet–Brillouin zones. This supercontinuum of edge states results from the coexistence and orthogonality of the localized flat-band modes and the edge states, allowing for continuous excitation of the latter without scattering into the bulk modes. Moreover, we show that these flat bands are perfectly immune to random variations in the on-site potential, regardless of how large the perturbations are, thus ensuring complete robustness of the edge modes to this type of disorder. We realized Floquet–Lieb insulators using 2D microring resonator lattices with perfect nearest-neighbor couplings. Transmission measurements and direct imaging of the scattered light distributions showed an edge mode supercontinuum spanning more than three microring free spectral ranges. The proposed Floquet–Lieb insulator can potentially be used to realize topological photonic devices with wide bandwidths and super robustness for applications in integrated quantum photonics and programmable photonic circuits.
{"title":"Wide edge state supercontinuum in a Floquet–Lieb topological photonic insulator","authors":"Hanfa Song, Tyler J. Zimmerling, Bo Leng, Vien Van","doi":"10.1063/5.0160174","DOIUrl":"https://doi.org/10.1063/5.0160174","url":null,"abstract":"Conventional topological photonic insulators typically have narrow nontrivial band gaps truncated by broad dispersive bulk bands, resulting in limited edge mode transmission bandwidths that can be exploited for potential applications. Here, we demonstrate a Floquet–Lieb topological photonic insulator with all flat bands that can support continuous edge mode transmission across multiple Floquet–Brillouin zones. This supercontinuum of edge states results from the coexistence and orthogonality of the localized flat-band modes and the edge states, allowing for continuous excitation of the latter without scattering into the bulk modes. Moreover, we show that these flat bands are perfectly immune to random variations in the on-site potential, regardless of how large the perturbations are, thus ensuring complete robustness of the edge modes to this type of disorder. We realized Floquet–Lieb insulators using 2D microring resonator lattices with perfect nearest-neighbor couplings. Transmission measurements and direct imaging of the scattered light distributions showed an edge mode supercontinuum spanning more than three microring free spectral ranges. The proposed Floquet–Lieb insulator can potentially be used to realize topological photonic devices with wide bandwidths and super robustness for applications in integrated quantum photonics and programmable photonic circuits.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135457219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pei-Jung Wu, Jing-Ting Hung, Cho-Fan Hsieh, Chii-Rong Yang, Chan-Shan Yang
Human exhaled gases contain a wide range of volatile organic compounds, offering the potential for detecting physiological, cardiovascular, and endocrine disorders. For instance, nitric oxide (NO) concentration can be indicative of chronic obstructive pulmonary disease. Analyzing exhaled gases provides a noninvasive approach to disease detection without posing any risks to individuals. While electronic sensors have been developed over the past two decades for NO detection at high temperatures, few studies have explored optical detection in the ultraviolet to visible light range, which may have adverse effects on the skin. In this study, we designed a split-ring resonator metamaterial tailored for operation within the terahertz (THz) frequency range. Specifically, the metamaterial was designed to resonate at the NO frequency of 0.257 THz. To enhance gas absorption capacity, we incorporated a composite film layer consisting of ZnTiO3 and reduced graphene oxide onto the metamaterial. By sintering ZnTiO3 powder at different temperatures, we achieved an increase in component sensitivity (ΔT/T) from 2% to 16.4%. Overall, the proposed metamaterial holds promise for both physical monitoring applications and the development of wearable electronic devices.
{"title":"High-selectivity terahertz metamaterial nitric oxide sensor based on ZnTiO3 perovskite membrane","authors":"Pei-Jung Wu, Jing-Ting Hung, Cho-Fan Hsieh, Chii-Rong Yang, Chan-Shan Yang","doi":"10.1063/5.0156772","DOIUrl":"https://doi.org/10.1063/5.0156772","url":null,"abstract":"Human exhaled gases contain a wide range of volatile organic compounds, offering the potential for detecting physiological, cardiovascular, and endocrine disorders. For instance, nitric oxide (NO) concentration can be indicative of chronic obstructive pulmonary disease. Analyzing exhaled gases provides a noninvasive approach to disease detection without posing any risks to individuals. While electronic sensors have been developed over the past two decades for NO detection at high temperatures, few studies have explored optical detection in the ultraviolet to visible light range, which may have adverse effects on the skin. In this study, we designed a split-ring resonator metamaterial tailored for operation within the terahertz (THz) frequency range. Specifically, the metamaterial was designed to resonate at the NO frequency of 0.257 THz. To enhance gas absorption capacity, we incorporated a composite film layer consisting of ZnTiO3 and reduced graphene oxide onto the metamaterial. By sintering ZnTiO3 powder at different temperatures, we achieved an increase in component sensitivity (ΔT/T) from 2% to 16.4%. Overall, the proposed metamaterial holds promise for both physical monitoring applications and the development of wearable electronic devices.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134934176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jielei Ni, Qianyi Wei, Yuquan Zhang, Jie Xu, Xi Xie, Yixuan Chen, Yanan Fu, Gengwei Cao, Xiaocong Yuan, Changjun Min
Femtosecond laser ablation has found wide-ranging applications in the surface structuring of nanoelectronics and nanophotonics devices. Traditionally, the inspection of the fabricated three-dimensional (3D) morphology was performed using a scanning electron microscope or atomic force microscopy in an ex situ manner after processing was complete. To quickly monitor and efficiently optimize the quality of surface fabrication, we developed an in situ method to accurately reconstruct the 3D morphology of surface micro-structures. This method is based on a triangulation optical system that utilizes structured illumination. The approach offers a super-resolution capacity, making it a powerful and non-invasive tool for quick in situ monitoring of surface ablation structures.
{"title":"Super-resolution three-dimensional structured illumination profilometry for <i>in situ</i> measurement of femtosecond laser ablation morphology","authors":"Jielei Ni, Qianyi Wei, Yuquan Zhang, Jie Xu, Xi Xie, Yixuan Chen, Yanan Fu, Gengwei Cao, Xiaocong Yuan, Changjun Min","doi":"10.1063/5.0165363","DOIUrl":"https://doi.org/10.1063/5.0165363","url":null,"abstract":"Femtosecond laser ablation has found wide-ranging applications in the surface structuring of nanoelectronics and nanophotonics devices. Traditionally, the inspection of the fabricated three-dimensional (3D) morphology was performed using a scanning electron microscope or atomic force microscopy in an ex situ manner after processing was complete. To quickly monitor and efficiently optimize the quality of surface fabrication, we developed an in situ method to accurately reconstruct the 3D morphology of surface micro-structures. This method is based on a triangulation optical system that utilizes structured illumination. The approach offers a super-resolution capacity, making it a powerful and non-invasive tool for quick in situ monitoring of surface ablation structures.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135849682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Chomet, T. Gabbrielli, D. Gacemi, F. Cappelli, L. Consolino, P. De Natale, F. Kapsalidis, A. Vasanelli, Y. Todorov, J. Faist, C. Sirtori
In quantum cascade laser frequency combs, the intensity distribution of the optical spectrum can be split into two well-separated lobes of longitudinal modes that, even when far apart, have a common phase relation and preserve equal frequency separation. The temporal dynamics of two lasers emitting at 4.4 and 8.1 µm operating in this bilobed regime are here investigated. The laser intensity shows a peculiar temporal behavior associated with the spectral features whereby, every half a round-trip, the total emitted power switches from one lobe to the other, with a perfect temporal anti-correlation. The anti-correlation between the lobes is also observed in the intensity noise figure of the emission. This coherent phenomenon arises from gain nonlinearities induced by spatial hole burning and the extremely fast gain dynamics typical of quantum cascade lasers.
{"title":"Anti-correlation phenomena in quantum cascade laser frequency combs","authors":"B. Chomet, T. Gabbrielli, D. Gacemi, F. Cappelli, L. Consolino, P. De Natale, F. Kapsalidis, A. Vasanelli, Y. Todorov, J. Faist, C. Sirtori","doi":"10.1063/5.0160103","DOIUrl":"https://doi.org/10.1063/5.0160103","url":null,"abstract":"In quantum cascade laser frequency combs, the intensity distribution of the optical spectrum can be split into two well-separated lobes of longitudinal modes that, even when far apart, have a common phase relation and preserve equal frequency separation. The temporal dynamics of two lasers emitting at 4.4 and 8.1 µm operating in this bilobed regime are here investigated. The laser intensity shows a peculiar temporal behavior associated with the spectral features whereby, every half a round-trip, the total emitted power switches from one lobe to the other, with a perfect temporal anti-correlation. The anti-correlation between the lobes is also observed in the intensity noise figure of the emission. This coherent phenomenon arises from gain nonlinearities induced by spatial hole burning and the extremely fast gain dynamics typical of quantum cascade lasers.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135811140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dong Wu, Than S. Saini, Shiyu Sun, Meng Huang, Qiang Fu, Thomas W. Hawkins, John Ballato, Anna C. Peacock
Wavelength conversion via four-wave mixing holds great promise for the construction of broadband and tunable light sources at wavelengths beyond 2 μm. In this work, we design and fabricate a tapered silicon core optical fiber with a dispersion profile that supports efficient conversion spanning the telecom band up to the edge of the mid-infrared spectral region over an extended propagation length. By pumping with a fiber laser centered around 1.99 μm, a tuning range of 690 nm has been measured, although simulations predict that a bandwidth of up to 1255 nm could be observed if a suitable seed source was available. Conversion efficiencies of ∼−30 dB have been obtained over a bandwidth of 380 nm when using an input pump power of only 6 dBm, with a maximum efficiency of −18 dB achieved when the conversion overlaps the strong Raman gain of the silicon core.
{"title":"Broadband, tunable wavelength conversion using tapered silicon fibers extending up to 2.4 <i>μ</i>m","authors":"Dong Wu, Than S. Saini, Shiyu Sun, Meng Huang, Qiang Fu, Thomas W. Hawkins, John Ballato, Anna C. Peacock","doi":"10.1063/5.0158734","DOIUrl":"https://doi.org/10.1063/5.0158734","url":null,"abstract":"Wavelength conversion via four-wave mixing holds great promise for the construction of broadband and tunable light sources at wavelengths beyond 2 μm. In this work, we design and fabricate a tapered silicon core optical fiber with a dispersion profile that supports efficient conversion spanning the telecom band up to the edge of the mid-infrared spectral region over an extended propagation length. By pumping with a fiber laser centered around 1.99 μm, a tuning range of 690 nm has been measured, although simulations predict that a bandwidth of up to 1255 nm could be observed if a suitable seed source was available. Conversion efficiencies of ∼−30 dB have been obtained over a bandwidth of 380 nm when using an input pump power of only 6 dBm, with a maximum efficiency of −18 dB achieved when the conversion overlaps the strong Raman gain of the silicon core.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134976950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Haindl, V. Bellemo, P. Rajendran, B. Tan, M. Liu, B. S. Lee, Q. Zhou, R. A. Leitgeb, W. Drexler, L. Schmetterer, M. Pramanik
Non-invasive imaging plays a crucial role in diagnosing and studying eye diseases. However, existing photoacoustic ophthalmoscopy (PAOM) techniques in mice have limitations due to handling restrictions, suboptimal optical properties, limited availability of light sources, and permissible light fluence at the retina. This study introduces an innovative approach that utilizes Rose Bengal, a contrast agent, to enhance PAOM contrast. This enables visualization of deeper structures, such as the choroidal vasculature and sclera in the mouse eye, using visible light. The integration of near-infrared-II (NIR-II) optical coherence tomography provides additional tissue contrast and insights into potential NIR-II PAOM capabilities. To optimize imaging, we developed a cost-effective 3D printable mouse eye phantom and a fully 3D printable tip/tilt mouse platform. This solution elevates PAOM to a user-friendly technology, which can be used to address pressing research questions concerning several ocular diseases, such as myopia, glaucoma, and/or age-related macular degeneration in the future.
{"title":"Visible light photoacoustic ophthalmoscopy and near-infrared-II optical coherence tomography in the mouse eye","authors":"R. Haindl, V. Bellemo, P. Rajendran, B. Tan, M. Liu, B. S. Lee, Q. Zhou, R. A. Leitgeb, W. Drexler, L. Schmetterer, M. Pramanik","doi":"10.1063/5.0168091","DOIUrl":"https://doi.org/10.1063/5.0168091","url":null,"abstract":"Non-invasive imaging plays a crucial role in diagnosing and studying eye diseases. However, existing photoacoustic ophthalmoscopy (PAOM) techniques in mice have limitations due to handling restrictions, suboptimal optical properties, limited availability of light sources, and permissible light fluence at the retina. This study introduces an innovative approach that utilizes Rose Bengal, a contrast agent, to enhance PAOM contrast. This enables visualization of deeper structures, such as the choroidal vasculature and sclera in the mouse eye, using visible light. The integration of near-infrared-II (NIR-II) optical coherence tomography provides additional tissue contrast and insights into potential NIR-II PAOM capabilities. To optimize imaging, we developed a cost-effective 3D printable mouse eye phantom and a fully 3D printable tip/tilt mouse platform. This solution elevates PAOM to a user-friendly technology, which can be used to address pressing research questions concerning several ocular diseases, such as myopia, glaucoma, and/or age-related macular degeneration in the future.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136059538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mustafa Yildirim, Ilker Oguz, Fabian Kaufmann, Marc Reig Escalé, Rachel Grange, Demetri Psaltis, Christophe Moser
Modern machine learning models use an ever-increasing number of parameters to train (175 × 109 parameters for GPT-3) with large datasets to achieve better performance. Optical computing has been rediscovered as a potential solution for large-scale data processing, taking advantage of linear optical accelerators that perform operations at lower power consumption. However, to achieve efficient computing with light, it remains a challenge to create and control nonlinearity optically rather than electronically. In this study, a reservoir computing approach (RC) is investigated using a 14-mm waveguide in LiNbO3 on an insulator as an optical processor to validate the benefit of optical nonlinearity. Data are encoded on the spectrum of a femtosecond pulse, which is launched into the waveguide. The output of the waveguide is a nonlinear transform of the input, enabled by optical nonlinearities. We show experimentally that a simple digital linear classifier using the output spectrum of the waveguide increases the classification accuracy of several databases by ∼10% compared to untransformed data. In comparison, a digital neural network (NN) with tens of thousands of parameters was required to achieve similar accuracy. With the ability to reduce the number of parameters by a factor of at least 20, an integrated optical RC approach can attain a performance on a par with a digital NN.
{"title":"Nonlinear optical feature generator for machine learning","authors":"Mustafa Yildirim, Ilker Oguz, Fabian Kaufmann, Marc Reig Escalé, Rachel Grange, Demetri Psaltis, Christophe Moser","doi":"10.1063/5.0158611","DOIUrl":"https://doi.org/10.1063/5.0158611","url":null,"abstract":"Modern machine learning models use an ever-increasing number of parameters to train (175 × 109 parameters for GPT-3) with large datasets to achieve better performance. Optical computing has been rediscovered as a potential solution for large-scale data processing, taking advantage of linear optical accelerators that perform operations at lower power consumption. However, to achieve efficient computing with light, it remains a challenge to create and control nonlinearity optically rather than electronically. In this study, a reservoir computing approach (RC) is investigated using a 14-mm waveguide in LiNbO3 on an insulator as an optical processor to validate the benefit of optical nonlinearity. Data are encoded on the spectrum of a femtosecond pulse, which is launched into the waveguide. The output of the waveguide is a nonlinear transform of the input, enabled by optical nonlinearities. We show experimentally that a simple digital linear classifier using the output spectrum of the waveguide increases the classification accuracy of several databases by ∼10% compared to untransformed data. In comparison, a digital neural network (NN) with tens of thousands of parameters was required to achieve similar accuracy. With the ability to reduce the number of parameters by a factor of at least 20, an integrated optical RC approach can attain a performance on a par with a digital NN.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"2014 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134935442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jiayu Zhao, Feifan Zhu, Yongpeng Han, Qining Wang, Li Lao, Xiaofeng Li, Yan Peng, Yiming Zhu
The next generation of all-optical computation platforms prefers the light-guiding-light (LGL) scheme inside a medium that envisions circuitry-free and rapidly reconfigurable systems powered by dynamic interactions between light beams. Currently, suitable LGL materials and corresponding mechanisms are in urgent need. In this work, we proposed ubiquitous air as a restorable LGL signal manipulation medium with transient air-plasma waveguide circuits. Briefly, by focusing femtosecond laser beams in free space, the created atmospheric plasma filament array via photoionization was able to guide terahertz (THz) pulses along its epsilon-near-zero zone with a 1/f-profile spectral response. Consequently, this achieved a time-domain integration of the THz pulse in broad bandwidth. When the pumping laser was sequentially turned off and on, this air-plasma multi-filament structure was erased and rebuilt within nano- and femto-seconds, respectively, allowing rapid and repeated rearrangements of the all-optical stage. Furthermore, this air-based LGL information processing approach is promising to pave the way toward all-optical calculations during free-space directional transmission of THz waves, in which way the delivered THz signal can be remotely controlled.
{"title":"Light-guiding-light-based temporal integration of broadband terahertz pulses in air","authors":"Jiayu Zhao, Feifan Zhu, Yongpeng Han, Qining Wang, Li Lao, Xiaofeng Li, Yan Peng, Yiming Zhu","doi":"10.1063/5.0158107","DOIUrl":"https://doi.org/10.1063/5.0158107","url":null,"abstract":"The next generation of all-optical computation platforms prefers the light-guiding-light (LGL) scheme inside a medium that envisions circuitry-free and rapidly reconfigurable systems powered by dynamic interactions between light beams. Currently, suitable LGL materials and corresponding mechanisms are in urgent need. In this work, we proposed ubiquitous air as a restorable LGL signal manipulation medium with transient air-plasma waveguide circuits. Briefly, by focusing femtosecond laser beams in free space, the created atmospheric plasma filament array via photoionization was able to guide terahertz (THz) pulses along its epsilon-near-zero zone with a 1/f-profile spectral response. Consequently, this achieved a time-domain integration of the THz pulse in broad bandwidth. When the pumping laser was sequentially turned off and on, this air-plasma multi-filament structure was erased and rebuilt within nano- and femto-seconds, respectively, allowing rapid and repeated rearrangements of the all-optical stage. Furthermore, this air-based LGL information processing approach is promising to pave the way toward all-optical calculations during free-space directional transmission of THz waves, in which way the delivered THz signal can be remotely controlled.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135963677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Miguel Soriano-Amat, Philippe Guay, Hugo F. Martins, Sonia Martin-Lopez, Miguel Gonzalez-Herraez, María R. Fernández-Ruiz, Jerome Genest
Time-expanded phase-sensitive optical time-domain reflectometry is a distributed optical fiber sensing technology based on dual-frequency combs that allows for dynamic and high spatial resolution measurements while maintaining reduced detection requirements. Since the formalization of the technique, different experimental schemes have been satisfactorily tested, with a general performance of cm-scale spatial resolution over hundreds of meters. In this article, we present an optimized scheme with enhanced energy and spectral efficiencies that allows reaching 5 mm spatial resolution. As compared to previous experimental approaches, the presented architecture is based on a free-running dual comb setup generated through pure electro-optical phase modulation. Besides, the introduction of an optical hybrid in the detection stage allows for doubling the spatial resolution while keeping the refresh rate and the sensing range unchanged.
{"title":"Millimetric spatial resolution time-expanded <i>ϕ</i>-OTDR","authors":"Miguel Soriano-Amat, Philippe Guay, Hugo F. Martins, Sonia Martin-Lopez, Miguel Gonzalez-Herraez, María R. Fernández-Ruiz, Jerome Genest","doi":"10.1063/5.0150991","DOIUrl":"https://doi.org/10.1063/5.0150991","url":null,"abstract":"Time-expanded phase-sensitive optical time-domain reflectometry is a distributed optical fiber sensing technology based on dual-frequency combs that allows for dynamic and high spatial resolution measurements while maintaining reduced detection requirements. Since the formalization of the technique, different experimental schemes have been satisfactorily tested, with a general performance of cm-scale spatial resolution over hundreds of meters. In this article, we present an optimized scheme with enhanced energy and spectral efficiencies that allows reaching 5 mm spatial resolution. As compared to previous experimental approaches, the presented architecture is based on a free-running dual comb setup generated through pure electro-optical phase modulation. Besides, the introduction of an optical hybrid in the detection stage allows for doubling the spatial resolution while keeping the refresh rate and the sensing range unchanged.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136059397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Vikas Remesh, Ria G. Krämer, René Schwarz, Florian Kappe, Yusuf Karli, Malte Per Siems, Thomas K. Bracht, Saimon Filipe Covre da Silva, Armando Rastelli, Doris E. Reiter, Daniel Richter, Stefan Nolte, Gregor Weihs
A scalable source of single photons is a key constituent of an efficient quantum photonic architecture. To realize this, it is beneficial to have an ensemble of quantum emitters that can be collectively excited with high efficiency. Semiconductor quantum dots hold great potential in this context due to their excellent photophysical properties. Spectral variability of quantum dots is commonly regarded as a drawback introduced by the fabrication method. However, this is beneficial to realize a frequency-multiplexed single-photon platform. Chirped pulse excitation, relying on the so-called adiabatic rapid passage, is the most efficient scheme to excite a quantum dot ensemble due to its immunity to individual quantum dot parameters. Yet, the existing methods of generating chirped laser pulses to excite a quantum emitter are bulky, lossy, and mechanically unstable, which severely hampers the prospects of a quantum dot photon source. Here, we present a compact, robust, and high-efficiency alternative for chirped pulse excitation of solid-state quantum emitters. Our simple plug-and-play module consists of chirped fiber Bragg gratings, fabricated via femtosecond inscription, to provide high values of dispersion in the near-infrared spectral range, where the quantum dots emit. We characterize and benchmark the performance of our method via chirped excitation of a GaAs quantum dot, establishing high-fidelity single-photon generation. Our highly versatile chirping module coupled to a photon source is a significant milestone toward realizing practical quantum photonic devices.
{"title":"Compact chirped fiber Bragg gratings for single-photon generation from quantum dots","authors":"Vikas Remesh, Ria G. Krämer, René Schwarz, Florian Kappe, Yusuf Karli, Malte Per Siems, Thomas K. Bracht, Saimon Filipe Covre da Silva, Armando Rastelli, Doris E. Reiter, Daniel Richter, Stefan Nolte, Gregor Weihs","doi":"10.1063/5.0164222","DOIUrl":"https://doi.org/10.1063/5.0164222","url":null,"abstract":"A scalable source of single photons is a key constituent of an efficient quantum photonic architecture. To realize this, it is beneficial to have an ensemble of quantum emitters that can be collectively excited with high efficiency. Semiconductor quantum dots hold great potential in this context due to their excellent photophysical properties. Spectral variability of quantum dots is commonly regarded as a drawback introduced by the fabrication method. However, this is beneficial to realize a frequency-multiplexed single-photon platform. Chirped pulse excitation, relying on the so-called adiabatic rapid passage, is the most efficient scheme to excite a quantum dot ensemble due to its immunity to individual quantum dot parameters. Yet, the existing methods of generating chirped laser pulses to excite a quantum emitter are bulky, lossy, and mechanically unstable, which severely hampers the prospects of a quantum dot photon source. Here, we present a compact, robust, and high-efficiency alternative for chirped pulse excitation of solid-state quantum emitters. Our simple plug-and-play module consists of chirped fiber Bragg gratings, fabricated via femtosecond inscription, to provide high values of dispersion in the near-infrared spectral range, where the quantum dots emit. We characterize and benchmark the performance of our method via chirped excitation of a GaAs quantum dot, establishing high-fidelity single-photon generation. Our highly versatile chirping module coupled to a photon source is a significant milestone toward realizing practical quantum photonic devices.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134936117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}