We review recent works in optical signal shaping and advanced characterization techniques within the framework of nonlinear fiber propagation. Specifically, we focus on the development of characterization methods based on the dispersive Fourier transform to monitor incoherent spectral broadening processes with enhanced resolution and sensitivity. In this framework, we also discuss recent studies of modulation instability in a noise-driven regime. Paired with suitable optical monitoring techniques, we show that controlled coherent optical seeding can be leveraged via several machine learning approaches to tailor and optimize incoherent spectral broadening dynamics.
Today’s quantum technology relies on the realization of large-scale non-classical systems in practical formats to enable quantum-accelerated computing, secure communications and enhanced sensing. Optical on-chip quantum frequency combs, characterized by many equidistantly spaced frequency modes, allow the storage of large amounts of quantum information and together with control mechanisms can provide practical large-scale quantum systems. In this contribution, we present recent advances on the controlled generation and use of quantum frequency combs for information processing. First, we demonstrate an electrically-pumped laser-integrated quantum light source of two- and high-dimensional maximally entangled photons. We exploit a hybrid InP-SiN approach which allows to include a filter, a gain section and a parametric photon pair source in a single system. Second, we demonstrate the generation of high-dimensional bi-photon quantum frequency combs with tunable entropies by exploiting a novel excitation technique and spectral filtering. Using this, we reveal unidirectional bosonic quantum walks, asymmetric energy transfer, and directional entanglement transport.
We demonstrate the first fully on-chip electrically-pumped laser-integrated quantum photonic source, which consists of a laser cavity, an InP gain section, and a Vernier filtering stage. This sub-millimeter-sized hybrid chip generates high-quality, low-noise (CAR ~80) entangled photon states with a remarkably high pair detection rate (~620 Hz) over four resonant modes within the C-band. We confirmed the realization of high-dimensional entangled states with fidelity of ~ 0.99 and visibility of ~ 96%. This fully integrated, practical, and field-deployable quantum light source brings scalability to applications ranging from quantum processing circuits, quantum internet to quantum satellite systems.
We generate high-dimensional bi-photon quantum frequency combs with tunable entropies exploiting the second-order nonlinearity of a periodically-poled lithium niobate waveguide through a novel pumping and filtering scheme. Using these quantum states with varying degrees of entanglement, we demonstrate unidirectional bosonic quantum walks, asymmetric energy transfer, and entanglement transport. Our non-maximally entangled quantum states can serve as excellent testbeds for several computational protocols. Moreover, we achieve the steering of the directionality in a scalable format, which enables a new control mechanism for quantum walks as well as novel modification means of joint probability distributions.
Spectral Hong-Ou-Mandel effect is experimentally revealed between a thermal field and a heralded state. We demonstrate that multi-photon components in heralded state get engaged in quantum interference which is manifested in improved visibilities for certain mean photon numbers of the thermal field. A theoretical relationship is derived for the visibility, showing its compound dependency on the mean photon number per pulse period within the thermal field and the thermal part of the heralded state. Relying on pulsed excitation, we demonstrate an experimental approach for time-efficient acquisition of visibility. The results of this research are of potential application to high-speed remote secret key-sharing and combating the security gaps arising from multi-photon contamination.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.