Cryogenic Optical Packaging Using Photonic Wire Bonds

TL;DR

This paper introduces a scalable cryogenic optical packaging method using photonic wire bonds, achieving low loss and robustness for quantum and low-temperature photonic applications.

Contribution

The work demonstrates a low-loss, scalable cryogenic packaging technique with robustness to thermal cycling and no active alignment needed.

Findings

Insertion loss less than 2 dB per connection at 970 mK

Robustness to thermal cycling

Compatibility with ultra-high vacuum environments

Abstract

We present the required techniques for the successful low loss packaging of integrated photonic devices capable of operating down to 970 mK utilizing photonic wire bonds. This scalable technique is shown to have an insertion loss of less than 2 dB per connection between a SMF-28 single mode fibre and a silicon photonic chip at these temperatures. This technique has shown robustness to thermal cycling and is ultra-high vacuum compatible without the need for any active alignment.