A Photonic Link at 4.7K with >1 GHz bandwidth towards an Optical Quantum Computing Interface

This paper presents the results of a performance evaluation of a photonic link in a cryogenic environment. The transmission from room temperature to 4.7K was achieved using a 904nm and 1310nm lasers with a bandwidth exceeding 1 GHz using both silicon-based and InGaAs-based commercial photodiodes. A reduction in DC photocurrent was observed. Moreover, the frequency response measurements demonstrate that both photodiodes improve their maximum bandwidth even when unbiased at cryogenic environment. Furthermore, this work presents a demonstration of photonic control of cryogenic electronics for quantum computing applications.