Non-volatile Tuning of Cryogenic Optical Resonators

TL;DR

This paper introduces a non-volatile tuning method for cryogenic photonic resonators using phase-change materials, enabling scalable quantum and physics applications at deep cryogenic temperatures.

Contribution

It demonstrates a novel non-volatile tuning technique for photonic resonators at sub-4K temperatures using integrated phase-change materials.

Findings

Achieved 10Gb/s resonant photonic modulation at cryogenic temperatures.

Enabled non-volatile resonance tuning at 4K using phase-change materials.

Facilitated scalable integration of thousands of resonators for quantum applications.

Abstract

Quantum computing, ultra-low-noise sensing, and high-energy physics experiments often rely on superconducting circuits or semiconductor qubits and devices operating at deep cryogenic temperatures (4K and below). Photonic integrated circuits and interconnects have been demonstrated for scalable communications and optical domain transduction in these systems. Due to energy and area constraints, many of these devices need enhanced light-matter interaction, provided by photonic resonators. A key challenge, however, for using these resonators is the sensitivity of resonance wavelength to process variations and thermal fluctuations. While thermo-optical tuning methods are typically employed at room temperature to mitigate this problem, the thermo-optic effect is ineffective at 4K. To address this issue, we demonstrate a non-volatile approach to tune the resonance of photonic resonators using integrated phase-change materials (PCMs) at cryogenic temperatures. In this work, we report a 10Gb/s free-carrier dispersion based resonant photonic modulator that can be tuned in a non-volatile fashion at sub-4K temperatures using a commercial silicon photonics process. This method paves the way for realizing scalable cryogenic integrated photonics with thousands of resonant devices for quantum and high-energy physics applications.