Generation and dynamical manipulation of polarization entangled Bell states by a silicon quantum photonic circuit

TL;DR

This paper presents a silicon quantum photonic circuit capable of generating, manipulating, and switching polarization entangled Bell states dynamically, advancing integrated quantum communication technologies.

Contribution

It introduces a novel integrated silicon photonic circuit that can generate and dynamically control polarization entangled Bell states in the telecom band.

Findings

Successfully generated polarization entangled Bell states on-chip.

Demonstrated dynamic switching between Bell states.

Achieved modulation speeds of several tens of kHz.

Abstract

A silicon quantum photonic circuit was proposed and demonstrated as an integrated quantum light source for telecom band polarization entangled Bell state generation and dynamical manipulation. Biphoton states were firstly generated in four silicon waveguides by spontaneous four wave mixing. They were transformed to polarization entangled Bell states through on-chip quantum interference and quantum superposition, and then coupled to optical fibers. The property of polarization entanglement in generated photon pairs was demonstrated by two-photon interferences under two non-orthogonal polarization bases. The output state could be dynamically switched between two polarization entangled Bell states, which was demonstrated by the experiment of simplified Bell state measurement. The experiment results indicate that its manipulation speed supported a modulation rate of several tens kHz, showing its potential on applications of quantum communication and quantum information processing requiring dynamical quantum entangled Bell state control.