Terahertz-Mediated Microwave-to-Optical Transduction

TL;DR

This paper analyzes a two-step electro-optic transducer scheme operating at THz frequencies, demonstrating near-unity efficiency and significant noise suppression, enabling quantum microwave-to-optical signal conversion with low noise.

Contribution

It introduces a novel two-step transduction scheme that reduces thermal noise and improves efficiency compared to direct methods.

Findings

Near-unity external efficiency achieved

Multi-order noise suppression demonstrated

Potential for quantum noise-limited microwave-to-optical transduction

Abstract

Transduction of quantum signals between the microwave and the optical ranges will unlock powerful hybrid quantum systems enabling information processing with superconducting qubits and low-noise quantum networking through optical photons. Most microwave-to-optical quantum transducers suffer from thermal noise due to pump absorption. We analyze the coupled thermal and wave dynamics in electro-optic transducers that use a two-step scheme based on an intermediate frequency state in the THz range. Our analysis, supported by numerical simulations, shows that the two-step scheme operating with a continuous pump offers near-unity external efficiency with a multi-order noise suppression compared to direct transduction. As a result, two-step electro-optic transducers may enable quantum noise-limited interfacing of superconducting quantum processors with optical channels at MHz-scale bitrates.