On-chip parallel processing of quantum frequency comb

Abstract

The frequency degree of freedom of optical photons has been recently explored for efficient quantum information processing. Significant reduction in hardware resources and enhancement of quantum functions can be expected by leveraging the large number of frequency modes. Here, we develope an integrated photonic platform for the generation and parallel processing of quantum frequency combs (QFCs). Cavity-enhanced parametric down-conversion with Sagnac configuration is implemented to generate QFCs with identical spectral distributions. On-chip quantum interference of different frequency modes is simultaneously realized with the same photonic circuit. High interference visibility is maintained across all frequency modes with the identical circuit setting. This enables the on-chip reconfiguration of QFCs. By deterministically separating QFCs without spectral filtering, we further demonstrate high-dimensional Hong-Ou-Mandel effect. Our work provides the critical step for the efficient implementation of quantum information processing with integrated photonics using the frequency degree of freedom.

Toward quantum networking with frequency-bin qudits

“…Here, the pump (780 nm) and photon pairs (1550 nm) occupy disparate optical bands, largely eliminating noise from Raman scattering and inadequate pump suppression, both of which contribute to lowering the coincidence-to-accidental ratio (CAR) in SFWM. 13,14 In another approach, by combining polarization splitter-rotators with a bidirectionally pumped Si microring, hyperentanglement can be realized, with simultaneous entanglement in both frequency-bin and polarization degrees of freedom. 15…”

High‐Dimensional Entanglement for Quantum Communication in the Frequency Domain

“…Entangled frequency states can also be generated in combination with entanglement in other DOFs like polarization, path [ 25 ] or even temporal, whenever the relevant time and frequency properties can be manipulated independently, because they refer to vastly different time scales. Such hyperentangled states can also be used to enlarge the dimensionality of the system, to generate cluster states [ 26 ] or to perform more advanced quantum gates.…”

Asymmetric Magnon Frequency Comb

“…Frequency combs are the spectra consisting of a series of discrete and equally spaced frequency components, which have been extensively studied both theoretically and experimentally due to their potential applications in metrology, atomic clocks, spectroscopy, attophysics, and quantum computing. − Although they were originally conceived in optics, huge enthusiasm for observing frequency combs in the community of magnonics and phononics is emerging. In particular, the magnon frequency comb (MFC) resulting from the nonlinear coupling between different-tone magnons has been reported in several magnetic systems recently. − Among them, the MFC induced by nonlinear magnon–skyrmion scattering is of particular interest because the inherent inhomogeneous magnetization of skyrmions can significantly enhance the nonlinearity and facilitate the generation of MFC .…”