Periodically poled thin-film lithium niobate ring Mach Zehnder coupling interferometer as an efficient quantum source of light

TL;DR

This paper introduces a novel ring Mach-Zehnder interferometer with a periodically poled lithium niobate waveguide that efficiently generates high-purity single photons and tunable squeezed light, advancing quantum photonics technology.

Contribution

It presents a new symmetric ring-Mach-Zehnder interferometer design integrating PPLN for efficient quantum light sources, achieving high squeezing levels and photon purity with low pump power.

Findings

Achieves > -12dB squeezing with sub-milliwatt pump power

Generates single photons with 99% purity and 94% heralding efficiency

Compatible with current fabrication technology

Abstract

Single photons and squeezed light are the two primary workhorses for quantum computation and quantum communication. Generating high-efficiency single photons with high purity and heralding efficiency is the prerequisite for photonic quantum computers. At the same time, generating high-efficiency scalable squeezed light is the prerequisite for continuous variable quantum computing along with sensing applications. Here, we propose a symmetric ring-Mach-Zehnder interferometer (RMZI), which includes a periodically poled lithium niobate (PPLN) waveguide as an efficient source of squeezed light and a single-photon source. We numerically show that our proposed design can generate tunable squeezed light with a squeezing level higher than -12dB with sub-milli-watt (mW) pump power. The proposed device can also generate single photons with purity as high as 99(95)% with heralding efficiency 94(99)% using only 20ps long pulses. Our proposed design is fully compatible with current fabrication technology.