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From ultra-noisy to ultra-stable: optimization of the optoelectronic laser lock

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arXiv 2025年

作者： Nakamura, Takuma Liu, Yifan Jin, Naijun Cheng, Haotian McLemore, Charles Hoghooghi, Nazanin Rakich, Peter Quinlan, Franklyn Time and Frequency Division National Institute of Standards and Technology 325 Broadway BoulderCO80305 United States Department of Physics University of Colorado Boulder 440 UCB BoulderCO80309 United States Department of Applied Physics Yale University New HavenCT06520 United States Electrical Computer and Energy Engineering University of Colorado BoulderCO80309 United States

We demonstrate thermal-noise-limited direct locking of a semiconductor distributed feedback (DFB) laser to a sub-1 mL volume, ultrastable optical cavity, enabling extremely compact and simple ultrastable laser systems. Using the optoelectronic laser locking method, we realize over 140 dB suppression of the DFB free-running laser noise at 10 Hz offset, a level we estimate to be ~ 70 dB greater than Pound-Drever-Hall locking can provide, and reach a phase noise level of -120 dBc/Hz at 200 kHz offset. We also demonstrate a new feedforward noise correction method that improves the quality of the heterodyne beat with an optical frequency comb by providing another 60 dB of laser noise rejection – a level that is 15 dB greater than predicted by current models. With feedforward, we transfer the cavity thermal noise limit across the comb spectrum despite the fact that the cavity-locked laser itself is noisy. These results establish a simple, low noise, compact approach to ultrastable laser locking that is compatible with integrated photonics, with applications in low phase noise microwave generation, sensing, and satellite ranging. © 2025, CC BY.

关键词： Keyways

Transition from Diffusive to Superdiffusive Transport in Carbon Nanotube Networks via Nematic Order Control

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arXiv 2023年

作者： Wais, Michael Bagsican, Filchito Renee G. Komatsu, Natsumi Gao, Weilu Serita, Kazunori Murakami, Hironaru Held, Karsten Kawayama, Iwao Kono, Junichiro Battiato, Marco Tonouchi, Masayoshi Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University Singapore Institute for Solid State Physics TU Wien Vienna1040 Austria Institute of Laser Engineering Osaka University Osaka Suita565-0871 Japan Department of Electrical and Computer Engineering Rice University HoustonTX77005 United States Department of Electrical and Computer Engineering University of Utah Salt Lake CityUT84112 United States Department of Physics and Astronomy Rice University HoustonTX77005 United States Department of Material Science and NanoEngineering Rice University HoustonTX77005 United States

The one-dimensional confinement of quasiparticles in individual carbon nanotubes (CNTs) leads to extremely anisotropic electronic and optical properties. In a macroscopic ensemble of randomly oriented CNTs, this anisotropy disappears together with other properties that make them attractive for certain device applications. The question however remains if not only anisotropy, but other types of behaviours are suppressed by disorder. Here, we compare the dynamics of quasiparticles under strong electric fields in aligned and random CNT networks using a combination of terahertz emission and photocurrent experiments and out-of-equilibrium numerical simulations. We find that the degree of alignment strongly influences the excited quasiparticles’ dynamics, rerouting the thermalisation pathways. This is, in particular, evidenced in the high-energy, high-momentum electronic population (probed through the formation of low energy excitons via exciton impact ionization) and the transport regime evolving from diffusive to superdiffusive. Copyright © 2023, The Authors. All rights reserved.

关键词： Anisotropy

All-Photonic Artificial Neural Network Processor Via Nonlinear Optics

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All-Photonic Artificial Neural Network Processor Via Nonline...

Conference on Lasers and Electro-Optics (CLEO)

作者： Jasvith Raj Basani Stefan Krastanov Mikkel Heuck Dirk R. Englund Department of Electrical and Computer Engineering Institute for Research in Electronics and Applied Physics and Joint Quantum Institute University of Maryland College Park MD USA Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology Cambridge Massachusetts USA DTU Fotonik Technical University of Denmark Lyngby Denmark

We propose an all-photonic architecture to accelerate linear matrix processing by encoding information in the amplitudes of frequency states. Our design is unique in providing a unitary, reversible mode of computation... 详细信息

ISBN: (数字)9781957171050

ISBN: (纸本)9781665466660

关键词： computer architecture Artificial neural networks Lasers and electrooptics Laser modes Encoding Nonlinear optics Electrooptical waveguides

Efficient Power Transfer via Induced Virtual Critical Coupling in an Overcoupled Silicon Nitride Microresonator

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Efficient Power Transfer via Induced Virtual Critical Coupli...

Conference on Lasers and Electro-Optics (CLEO)

作者： Jakob Hinney Seunghwi Kim Graydon J. K. Flatt Ipshita Datta Andrea Alù Michal Lipson Department of Electrical Engineering Columbia University New York NY USA Photonics Initiative Advanced Science Research Center City University of New York New York NY USA Department of Applied Physics and Applied Mathematics Columbia University New York NY USA Physics Program Graduate Center City University of New York New York NY USA

We induce virtual critical coupling in an overcoupled photonic microresonator using complex-frequency pulses. We observe efficient cavity storage as an incident pulse of time constant 138 ps suppresses the resonant tr... 详细信息

ISBN: (纸本)9781957171258

关键词： Continuous wave operation Coupled mode theory Electrooptical modulators Optical resonators Pulse shaping Silicon nitride

Giant Deep-Ultraviolet Circular Dichroism in Synthetic Architectures of Ordered Carbon Nanotubes

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Giant Deep-Ultraviolet Circular Dichroism in Synthetic Archi...

Conference on Lasers and Electro-Optics (CLEO)

作者： Jacques Doumani Minhan Lou Oliver Dewey Nina Hong Jichao Fan Andrey Baydin Matteo Pasquali Yohei Yomogida Kazuhiro Yanagi Riichiro Saito Junichiro Kono Weilu Gao Department of Electrical and Computer Engineering Rice University Houston TX USA Applied Physics Graduate Program Smalley-Curl Institute Rice University Houston TX USA Department of Electrical and Computer Engineering The University of Utah Salt Lake City UT USA Carbon Hub Rice University Houston TX USA Department of Chemical and Biomolecular Engineering Rice University Houston TX USA J.A. Woollam Co. Lincoln NE USA The Smalley-Curl Institute Rice University Houston TX USA Department of Chemistry Rice University Houston TX USA Department of Materials Science and NanoEngineering Rice University Houston TX USA Department of Physics and Astronomy Tokyo Metropolitan University Tokyo Japan Department Physics Tohoku University Sendai Japan Department Physics and Astronomy Rice University Houston TX USA

We demonstrate tunable, giant, and structure-induced deep-ultraviolet circular dichroism in macroscopically chiral assemblies of racemic carbon nanotubes prepared using two approaches: mechanical-rotation-assisted vac... 详细信息

ISBN: (纸本)9781957171258

关键词： Carbon nanotubes Chiral media Dichroism Graphene Optical activity Quantum information

Quantum Circuit for Non-Unitary Linear Transformation of Basis Sets

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arXiv 2025年

作者： Zhu, Guorui Bierman, Joel Lu, Jianfeng Li, Yingzhou School of Mathematical Sciences Fudan University China Electrical and Computer Engineering North Carolina State University United States Department of Mathematics Department of Physics Department of Chemistry Duke University United States School of Mathematical Sciences Shanghai Key Laboratory for Contemporary Applied Mathematics Fudan University Key Laboratory of Computational Physical Sciences Ministry of Education China

This paper introduces a novel approach to implementing non-unitary linear transformations of basis on quantum computational platforms, a significant leap beyond the conventional unitary methods. By integrating Singular Value Decomposition (SVD) into the process, the method achieves an operational depth of O(n) with about n ancilla qubits, enhancing the computational capabilities for analyzing fermionic systems. The non-unitarity of the transformation allows us to transform a wave function from one basis to another, which can span different spaces. By this trick, we can calculate the overlap of two wavefunctions that live in different (but non-distinct Hilbert subspaces) with different basis representations. This provides the opportunity to use state specific ansatzes to calculate different energy eigenstates under orbital-optimized settings and may improve the accuracy when computing the energies of multiple eigenstates simultaneously in VQE or other framework. It allows for a deeper exploration of complex quantum states and phenomena, expanding the practical applications of quantum computing in physics and chemistry. © 2025, CC BY.

关键词： Wave functions

ManQala: Game-Inspired Strategies for Quantum State engineering

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arXiv 2023年

作者： Danaci, Onur Zhang, Wenlei Coleman, Robert Djakam, William Amoo, Michaela Glasser, Ryan T. Kirby, Brian T. N'Gom, Moussa Searles, Thomas A. IBM-HBCU Quantum Center Howard University WashingtonDC20059 United States Instituut-Lorentz Universiteit Leiden Leiden2300 RA Netherlands Department of Physics & Engineering Physics Tulane University New OrleansLA70118 United States Department of Electrical & Computer Engineering University of Alabama-Birmingham BirminghamAL35233 United States Devcom Army Research Laboratory AdelphiMD20783 United States Department of Physics Applied Physics and Astronomy Rensselaer Polytechnic Institute TroyNY12180 United States Department of Electrical & Computer Engineering University of Illinois Chicago ChicagoIL60607 United States

The ability to prepare systems in specific target states through quantum engineering is essential for realizing the new technologies promised by a second quantum revolution. Here, we recast the fundamental problem of state preparation in high-dimensional Hilbert spaces as ManQala, a quantum game inspired by the West African sowing game mancala. Motivated by optimal gameplay in solitaire mancala, where nested nearest-neighbor permutations and actions evolve the state of the game board to its target configuration, ManQala acts as a pre-processing approach for deterministically arranging particles in a quantum control problem. Once pre-processing with ManQala is complete, existing quantum control methods are applied, but now with a reduced search space. We find that ManQala-type strategies match, or outperform, competing approaches in terms of final state variance even in small-scale quantum state engineering problems where we expect the slightest advantage, since the relative reduction in search space is the least. These results suggest that ManQala provides a rich platform for designing control protocols relevant to near-term intermediate-scale quantum technologies. © 2023, CC BY.

关键词： Control theory

Study of Novel Photodetectors and Electronics to Enhance Coincidence Time Resolution of BGO-based PET Detectors

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Study of Novel Photodetectors and Electronics to Enhance Coi...

IEEE Symposium on Nuclear Science (NSS/MIC)

作者： Andrea Gonzalez-Montoro Shirin Pourashraf Joshua W Cates Craig S Levin Department of Radiology Stanford University Stanford CA USA Applied Nuclear Physics Program Lawrence Berkeley National Laboratory Berkeley CA USA Departments of Radiology Molecular Imaging Program Bioengineering Physics and Electrical Engineering Stanford University CA USA

Developing high sensitivity multiparametric medical imaging tools constitutes one of the main research topics in radionuclide *** time-of-flight positron emission tomography (TOF-PET) scanners have shown potential in this context. One of the most attractive solutions that have been proposed to improve the coincidence time resolution (CTR) of TOF-PET scanners includes exploiting the small population of promptly emitted light photons (i.e., Cherenkov photons). Bismuth germanate (BGO) is a legacy detection material for PET which exhibits a moderate Cherenkov yield. which new advancements in ultra-violet (UV) light sensitive photosensor technologies and associated detection techniques can exploit for fast timing. It has been demonstrated that exploiting the BGO–Cherenkov component may simultaneously facilitate high 511 keV photon detection sensitivity with excellent CTR, thus enabling high sensitivity, low cost TOF-PET systems. Accessing the timing information from these Cherenkov photons requires enhanced photodetector technology combined with low noise and fast readout electronics, as well as specific data post-processing *** this summary, we report the CTR evaluation of different length BGO crystals coupled to UV enhanced SiPMs and custom designed electronics. Average CTR values of 156 ± 6, 188 ± 5, 228 ± 8 and 297 ± 8 ps CTR FWHM have been achieved for 3 × 3 × 3, × 5, × 10, and × 15 mm 3 BGO crystal with chemically processed surface finishes.

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Classification of Single Photons in Higher-Order Spatial Modes via Convolutional Neural Networks

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arXiv 2024年

作者： Bart, Manon P. Dawanse, Sita Savino, Nicholas J. Tran, Viet Wang, Tianhong Lohani, Sanjaya Nefissi, Farris Bassene, Pascal N'gom, Moussa Glasser, Ryan T. Department of Physics and Engineering Physics Tulane University New OrleansLA70118 United States NASA Goddard Space Flight Center GreenbeltMD20771 United States Department of Physics Applied Physics and Astronomy Rensselaer Polytechnic Institute 110 Eighth St TroyNY12180 United States Center for Biotechnology and Interdisciplinary Studies Rensselaer Polytechnic Institute 1623 15th St TroyNY12180 United States Department of Electrical and Computer Engineering Southern Methodist University DallasTX75205 United States

Spatial modes are a promising candidate for encoding information for classical and quantum optical communication due to their potential high information capacity. Unfortunately, compensation of the wavefront upon propagation through the atmosphere is necessary to benefit from advantages spatial modes offer. In this work, we leverage the success of convolutional networks in denoising and classifying images to improve information transfer of spatial modes. Hermite-Gauss, Laguerre-Gauss, and Ince-Gauss modes are experimentally generated using single photons and imaged. A denoising autoencoder corrects for turbulence effects on the wavefront, followed by a convolutional neural network to classify mode orders. The model achieves a 99.2 % classification accuracy across all modes, and Hermite-Gauss modes exhibited the highest individual mode accuracy. As the convolutional networks rely solely on intensity, they offer an efficient and cost-effective tool for optical communication systems in the single photon limit. © 2024, CC BY.

关键词： Optical communication