# Temporally Asymmetric Bi-photon States in Cavity Enhanced Optical Parametric Processes

## TL;DR

This paper demonstrates the control of time-energy entanglement in bi-photon states generated in microcavities by manipulating cavity mode densities, enabling advanced quantum state engineering on integrated platforms.

## Contribution

It introduces a method to prepare asymmetric temporal bi-photon states via mode density modification using Rayleigh scattering in microcavities, enhancing quantum control capabilities.

## Key findings

- Successfully generated asymmetric bi-photon states with tailored temporal wavefunctions.
- Revealed exotic coherence properties of the engineered states.
- Showed potential for on-chip continuous variable quantum state engineering.

## Abstract

Generation and control of quantum states of light on an integrated platform has become an essential tool for scalable quantum technologies. Chip scale sources such as nonlinear optical microcavities have been demonstrated to efficiently generate entangled bi-photon states. However these systems have little control over the continuous variable time-energy entanglement of the photons. We demonstrate such control by preparing bi-photon states with asymmetric temporal wavefunctions by selectively modifying the density of states of the cavity modes taking part in the interaction using Rayleigh scattering-induced strong coupling of optical modes of a resonator. These states reveal exotic coherence properties and show a path forward for continuous variable quantum state engineering on a chip.