arXiv subjects

Melissa A. Guidry

Publications and source records attributed to Melissa A. Guidry.

17 recordsLinked to original sources

arXiv2026

Singly resonant InGaP microresonators for efficient, low-threshold second-order nonlinear optics

Strong $χ^{(2)}$ interactions at low optical powers are key to scalable nonlinear and quantum photonics. Although doubly resonant microresonators exhibit exceptional efficiencies, they require simultaneous resonance and phase matching of widely separated optical frequencies, making them inherently sensitive to fabrication and operating conditions. Singly resonant cavities eliminate this constraint by resonating at only the fundamental frequency while the second-harmonic field propagates in a single pass, but they have traditionally sacrificed nonlinear efficiency. Here, we demonstrate a singly resonant InGaP-on-insulator microresonator that overcomes this tradeoff. Combining the large $χ^{(2)}$ nonlinearity of InGaP with high-quality-factor resonators, we achieve efficient and widely tunable second-harmonic generation, broadband quantum-frequency-comb generation, and low-threshold optical parametric oscillation. Unlike conventional centimeter-long singly resonant devices, our millimeter-scale InGaP devices deliver nonlinear performance comparable to, and even exceeding, doubly resonant systems. By overcoming the conventional efficiency-robustness tradeoff of singly resonant devices, this work opens a new route to low-power, broadband, and widely tunable $χ^{(2)}$ nonlinear and quantum photonics.

physics.optics↗

arXiv2026

Integrated Dual-Resonator Architecture for Telecom Photon-Memory Entanglement

Scalable quantum networks require the efficient generation and storage of entanglement between photonic qubits and quantum memories. Quantum repeaters based on absorptive rare-earth-ion photonic memories offer a promising route toward highly multiplexed quantum networking, but unifying spectrally matched photon sources and quantum memories within a common architecture remains a major challenge. Here we demonstrate an integrated photonic architecture for telecom photon-memory entanglement generation based on dual self-similar silicon carbide microring resonators. Connected by a fiber link, one resonator operates as an entangled photon-pair source, while the other functions as a cavity-enhanced atomic-frequency-comb quantum memory. The memory resonator reaches an ensemble cooperativity of 1.9 after hyperfine initialization and is spectrally matched to the source, enabling storage of entangled telecom photons without spectral modification. We generate and characterize photon-memory entanglement from a quantum interference visibility preserved before and after storage. Harnessing the strong source correlations and the high multimode capacity of the memory, we access high-dimensional entanglement spanning 63 temporal modes, reaching a maximum photon information efficiency of 5.1 Ebits per detected photon and a peak on-chip photon-memory entanglement rate of 5.6 kEbits per second. These results establish a route toward chip-scale quantum networking hardware operating over telecommunications infrastructure.

quant-ph↗

arXiv2026

A Wafer-Scale Heterogeneous III-V-on-Silicon Nitride Quantum Photonic Platform

Heterogeneous integration of gain and strongly nonlinear materials with ultra-low-loss silicon nitride (SiN) photonics offers a route to scalable quantum circuits, but concurrent wafer-scale manufacturability, low interlayer loss, and high performance have been challenging to realize. Here we demonstrate a wafer-scale III-V-on-SiN quantum photonic platform that directly integrates III-V layers to foundry-fabricated SiN circuits. The SiN layer provides 200-300 nm thick waveguides with $<1$ dB/m loss and a mature passive photonics ecosystem, while III-V materials provide large $χ^{\left(2\right)}$ and $χ^{\left(3\right)}$ nonlinearities for parametric gain, frequency conversion and quantum light generation. Adiabatic interlayer couplers yield $<25$ mdB loss to InGaP waveguides and resonators with intrinsic quality factors exceeding $10^6$, enabling $15\times$ brighter entanglement sources and efficient nonlinear conversion on SiN. Integrated components--including low-loss beam splitters, waveguide crossers, and tunable interferometers--are complemented by III-V lasers and InP photodetectors with amplifiers achieving up to $99^{+1}_{-12}\%$ quantum efficiency and $3$ GHz bandwidth. This architecture unites ultra-efficient sources, nonlinear elements and detectors on a wafer-scale, low-loss platform, establishing a path toward large-scale, low-noise quantum photonic systems.

physics.optics↗

arXiv2026

Noise-Resilient Quantum Metrology

Quantum metrology seeks to leverage the richness of quantum systems for making better measurements than are possible using only classical resources in order to gain a ``quantum advantage''. Quantum metrology schemes must also be resilient against noise to be useful in practice. Simultaneously achieving quantum advantage and noise resilience requires an end-to-end analysis of quantum measurement schemes to assess their theoretical sensitivity, feasibility, and noise robustness. We demonstrate this approach through the development of a novel optical interferometer based on squeezed vacuum light. We propose a scheme that relies on a nonlinear phase estimation procedure, which allows us to shift the frequency of noise away from the signal band, resulting in a high degree of noise resilience. This enables us to achieve sensitivity with Heisenberg scaling in the lossless limit and sensitivity below the standard quantum limit (SQL) in practice. It also enables the first experimental demonstration of quantum-optimal Bayesian signal estimation in a balanced interferometer. We expect this end-to-end design approach to enable the development of a variety of useful quantum measurement protocols going forward.

quant-ph↗

arXiv2025

Quadrature-Dependent Lattice Dynamics of Dissipative Microcombs

The study of coupled networks with parametric amplification of the vacuum fluctuations has garnered increasing interest due to its intricate physics and potential applications. In these systems, parametric interactions lead to beam-splitter coupling and two-mode squeezing, creating quadrature-dependent dynamics. These systems can be modeled as bosonic networks, arrays or lattices, exhibiting exotic effects such as unidirectional amplification and non-Hermitian chiral transport which influence multimode squeezing. However, exploring and controlling these network dynamics experimentally in all-optical systems remains challenging. Recent advancements in integrated nonlinear micro-resonators, known as Kerr microcombs, enable the generation and control of broadband high-repetition pulses on microchips. Kerr microcombs exhibit intriguing nonlinear dynamics, where coherent photons occupy discrete spectral lines, leading to multimode squeezed vacuum states. In this work, we explore the lattice dynamics of vacuum fluctuations driven by dissipative Kerr microcombs. We design a photonic chip where a spontaneously emergent pair of pulses creates extended multimode states of parametrically amplified vacuum fluctuations. These states exhibit oscillatory dynamics, with implications on squeezing and secondary comb formation. By employing integrated micro-heaters, we tune the vacuum fluctuations to eliminate the oscillations, establishing a fundamental connection between non-Hermitian lattice symmetries and Kerr combs, paving the way for exotic quadrature-dependent optical networks with broad implications for quantum and classical photonic technologies.

physics.optics↗

arXiv2025

Mesoscopic cavity quantum electrodynamics with phase-disordered emitters in a Kerr nonlinear resonator

The field of cavity quantum electrodynamics (QED) has seen a recent resurgence of interest in few- and many-body physics owing to the realization that the breaking of symmetries and the presence of disorder can give rise to entirely new phenomena. Here we demonstrate a few-emitter cavity QED system capable of realizing new Hamiltonians in quantum optics based on breaking of symmetries and the realization of an in situ Kerr nonlinearity. Our experiment relies on a high-finesse silicon carbide whispering gallery mode resonator hosting an ensemble of silicon vacancy color centers. The simultaneous presence of spectral and spatial disorder of the mesoscopic atom system gives rise to emergent chirality, and the optical nonlinearity of the silicon carbide host crystal enables the observation of atom-photon correlations induced by a four-photon nonlinear process. This work demonstrates the potential for solid state defect systems to realize emerging proposals and to study fundamental physics in quantum electrodynamics.

quant-ph↗

arXiv2024

Cavity Quantum Electrodynamics in Finite-Bandwidth Squeezed Reservoir

Light-matter interaction with squeezed vacuum has received much interest for the ability to enhance the native interaction strength between an atom and a photon with a reservoir assumed to have an infinite bandwidth. Here, we study a model of parametrically driven cavity quantum electrodynamics (cavity QED) for enhancing light-matter interaction while subjected to a finite-bandwidth squeezed vacuum drive. Our method is capable of unveiling the effect of relative bandwidth as well as squeezing required to observe the anticipated anti-crossing spectrum and enhanced cooperativity without the ideal squeezed bath assumption. Furthermore, we analyze the practicality of said models when including intrinsic photon loss due to resonators imperfection. With these results, we outline the requirements for experimentally implementing an effectively squeezed bath in solid-state platforms such as InAs quantum dot cavity QED such that \textit{in situ} control and enhancement of light-matter interaction could be realized.

quant-ph↗

arXiv2023

Titanium:Sapphire-on-insulator for broadband tunable lasers and high-power amplifiers on chip

Titanium:Sapphire (Ti:Sa) lasers have been essential for advancing fundamental research and technological applications. Ti:Sa lasers are unmatched in bandwidth and tuning range, yet their use is severely restricted due to their large size, cost, and need for high optical pump powers. Here, we demonstrate a monocrystalline Ti:Sa-on-insulator (Ti:SaOI) photonics platform which enables dramatic miniaturization, cost-reduction, and scalability of Ti:Sa technology. First, through fabrication of low-loss whispering gallery mode resonators, we realize a Ti:Sa laser operating with an ultra-low lasing threshold of 290 $μ$W. Then, through orders-of-magnitude improvement in mode confinement in Ti:SaOI waveguides, we realize the first integrated solid-state (i.e., non-semiconductor) optical amplifier operating below 1 $μ$m, with an ultra-wide bandwidth of 700 - 950 nm and peak gain of 64 dB/cm. We demonstrate unprecedented 17 dB distortion-free amplification of picosecond pulses to up to 2.3 nJ pulse energy, corresponding to a peak power of 1.0 kW. Finally, we demonstrate the first tunable integrated Ti:Sa laser, featuring narrow linewidths and a 24.7 THz tuning range, which, for the first time, can be pumped with low-cost, miniature, off-the-shelf green laser diodes. This opens doors to new modalities of Ti:Sa lasers (now occupying a footprint less than 0.15 mm$^2$), such as massively-scalable Ti:Sa laser array systems for a variety of applications. As a proof-of-concept demonstration, we employ a Ti:SaOI laser array as the sole optical control for a cavity quantum electrodynamics experiment with artificial atoms in silicon carbide. This work is a key step towards the democratization of Ti:Sa technology through a three orders-of-magnitude reduction in cost and footprint, as well as the introduction of solid-state broadband amplification of sub-micron wavelength light.

physics.optics↗

arXiv2023

Inverse-designed Silicon Carbide Quantum and Nonlinear Photonics

Inverse design has revolutionized the field of photonics, enabling automated development of complex structures and geometries with unique functionalities unmatched by classical design. However, the use of inverse design in nonlinear photonics has been limited. In this work, we demonstrate quantum and classical nonlinear light generation in silicon carbide nanophotonic inverse-designed Fabry-Pérot cavities. We achieve ultra-low reflector losses while targeting a pre-specified anomalous dispersion to reach optical parametric oscillation. By controlling dispersion through inverse design, we target a second-order phase-matching condition to realize second- and third-order nonlinear light generation in our devices, thereby extending stimulated parametric processes into the visible spectrum. This first realization of computational optimization for nonlinear light generation highlights the power of inverse design for nonlinear optics, in particular when combined with highly nonlinear materials such as silicon carbide.

physics.optics↗

arXiv2022

Optical superradiance of a pair of color centers in an integrated silicon-carbide-on-insulator microresonator

An outstanding challenge for color center-based quantum information processing technologies is the integration of optically-coherent emitters into scalable thin-film photonics. Here, we report on the integration of near-transform-limited silicon vacancy (V$_{\text{Si}}$) defects into microdisk resonators fabricated in a CMOS-compatible 4H-Silicon Carbide-on-Insulator platform. We demonstrate a single-emitter cooperativity of up to 0.8 as well as optical superradiance from a pair of color centers coupled to the same cavity mode. We investigate the effect of multimode interference on the photon scattering dynamics from this multi-emitter cavity quantum electrodynamics system. These results are crucial for the development of quantum networks in silicon carbide and bridge the classical-quantum photonics gap by uniting optically-coherent spin defects with wafer-scalable, state-of-the-art photonics.

quant-ph↗

arXiv2021

Inverse-designed multi-dimensional silicon photonic transmitters

Modern microelectronic processors have migrated towards parallel computing architectures with many-core processors. However, such expansion comes with diminishing returns exacted by the high cost of data movement between individual processors. The use of optical interconnects has burgeoned as a promising technology that can address the limits of this data transfer. While recent pushes to enhance optical communication have focused on developing wavelength-division multiplexing technology, this approach will eventually saturate the usable bandwidth, and new dimensions of data transfer will be paramount to fulfill the ever-growing need for speed. Here we demonstrate an integrated intra- and inter-chip multi-dimensional communication scheme enabled by photonic inverse design. Using inverse-designed mode-division multiplexers, we combine wavelength- and mode- multiplexing and send massively parallel data through nano-photonic waveguides and optical fibres. Crucially, as we take advantage of an orthogonal optical basis, our approach is inherently scalable to a multiplicative enhancement over the current state of the art.

physics.app-ph↗

arXiv2021

Quantum optics of soliton microcombs

Soliton microcombs -- phase-locked microcavity frequency combs -- have become the foundation of several classical technologies in integrated photonics, including spectroscopy, LiDAR, and optical computing. Despite the predicted multimode entanglement across the comb, experimental study of the quantum optics of the soliton microcomb has been elusive. In this work, we use second-order photon correlations to study the underlying quantum processes of soliton microcombs in an integrated silicon carbide microresonator. We show that a stable temporal lattice of solitons can isolate a multimode below-threshold Gaussian state from any admixture of coherent light, and predict that all-to-all entanglement can be realized for the state. Our work opens a pathway toward a soliton-based multimode quantum resource.

physics.optics↗

arXiv2020

Integrated quantum photonics with silicon carbide: challenges and prospects

Optically-addressable solid-state spin defects are promising candidates for storing and manipulating quantum information using their long coherence ground state manifold; individual defects can be entangled using photon-photon interactions, offering a path toward large scale quantum photonic networks. Quantum computing protocols place strict limits on the acceptable photon losses in the system. These low-loss requirements cannot be achieved without photonic engineering, but are attainable if combined with state-of-the-art nanophotonic technologies. However, most materials that host spin defects are challenging to process: as a result, the performance of quantum photonic devices is orders of magnitude behind that of their classical counterparts. Silicon carbide (SiC) is well-suited to bridge the classical-quantum photonics gap, since it hosts promising optically-addressable spin defects and can be processed into SiC-on-insulator for scalable, integrated photonics. In this Perspective, we discuss recent progress toward the development of scalable quantum photonic technologies based on solid state spins in silicon carbide, and discuss current challenges and future directions.

quant-ph↗

arXiv2020

Spectrally reconfigurable quantum emitters enabled by optimized fast modulation

The ability to shape photon emission facilitates strong photon-mediated interactions between disparate physical systems, thereby enabling applications in quantum information processing, simulation and communication. Spectral control in solid state platforms such as color centers, rare earth ions, and quantum dots is particularly attractive for realizing such applications on-chip. Here we propose the use of frequency-modulated optical transitions for spectral engineering of single photon emission. Using a scattering-matrix formalism, we find that a two-level system, when modulated faster than its optical lifetime, can be treated as a single-photon source with a widely reconfigurable photon spectrum that is amenable to standard numerical optimization techniques. To enable the experimental demonstration of this spectral control scheme, we investigate the Stark tuning properties of the silicon vacancy in silicon carbide, a color center with promise for optical quantum information processing technologies. We find that the silicon vacancy possesses excellent spectral stability and tuning characteristics, allowing us to probe its fast modulation regime, observe the theoretically-predicted two-photon correlations, and demonstrate spectral engineering. Our results suggest that frequency modulation is a powerful technique for the generation of new light states with unprecedented control over the spectral and temporal properties of single photons.

quant-ph↗

arXiv2020

Optical parametric oscillation in silicon carbide nanophotonics

Silicon carbide (SiC) is rapidly emerging as a leading platform for the implementation of nonlinear and quantum photonics. Here, we find that commercial SiC, which hosts a variety of spin qubits, possesses low optical absorption that can enable SiC integrated photonics with quality factors exceeding $10^7$. We fabricate microring resonators with quality factors as high as 1.1 million, and observe low-threshold (8.5 $\pm$ 0.5 mW) optical parametric oscillation as well as optical microcombs spanning 200 nm. Our demonstration is an essential milestone in the development of photonic devices that harness the unique optical properties of SiC, paving the way toward the monolithic integration of nonlinear photonics with spin-based quantum technologies.

physics.optics↗

arXiv2017

Characterization of frequency stability in EIT-based atomic clocks using a differential detection scheme

We investigate a recently proposed scheme for differential detection of the magneto-optical rotation effect and its application to electromagnetically induced transparency (EIT) atomic clocks. This scheme utilizes a linearly polarized bichromatic laser field that is EIT-resonant with alkali atoms. The results of our study reveal that the suppression of the laser noise can substantially improve the signal-to-noise ratio in EIT atomic clocks. Our preliminary results demonstrate an order of magnitude improvement in clock stability under some conditions when incorporating the differential detection scheme

physics.ins-det↗

arXiv2017

Multi-pass configuration for Improved Squeezed Vacuum Generation in Hot Rb Vapor

We study a squeezed vacuum field generated in hot Rb vapor via the polarization self-rotation effect. Our previous experiments showed that the amount of observed squeezing may be limited by the contamination of the squeezed vacuum output with higher-order spatial modes, also generated inside the cell. Here, we demonstrate that the squeezing can be improved by making the light interact several times with a less dense atomic ensemble. With optimization of some parameters we can achieve up to -2.6 dB of squeezing in the multi-pass case, which is 0.6 dB improvement compared to the single-pass experimental configuration. Our results show that other than the optical depth of the medium, the spatial mode structure and cell configuration also affect the squeezing level.

physics.atom-ph↗