All envisaged practical implementations of cryogenic processors, including quantum computers and classical processors based on single flux quantum (SFQ) signals, require massive data transfer from and to classical high performance computers (HPCs). Cryogenic computing has recently become a very hot topic, including superconducting quantum computers (QCs), and classical processors based on single flux quantum (SFQ) signals. All envisaged practical implementations of cryogenic processors require massive data transfer from and to classical HPCs. The project aCryComm aims to develop building blocks for cryogenic photonics interconnects and eventually enable this challenging data transfer. The long-term goal is the development of an open-access platform to integrate classical optical interfaces based on low-loss silicon photonics, plasmonics, and nano light sources together with superconducting photonic and electronic devices, including SFQ-based co-processors for HPCs and for QCs.
We develop schemes to generate, manipulate and detect single photons at various frequencies including telecom wavelengths. With detectors based on superconducting nanowires we combine very high detection efficiency with high time resolution and very low noise levels. We demonstrate on-chip implementation of single photon techniques as well as long distance implementations using deployed optical fibers.
Quantum communication applications require a scalable approach to integrate bright sources of entangled photon-pairs in complex on-chip quantum circuits. Currently, the most promising sources are based on III/V semiconductor quantum dots. However, complex photonic circuitry is mainly achieved in silicon photonics due to the tremendous technological challenges in circuit fabrication. We take the best of both worlds by developing a new hybrid on-chip nanofabrication approach. We demonstrate for the first time on-chip generation, spectral filtering, and routing of single-photons from selected single and multiple III/V semiconductor nanowire quantum emitters all deterministically integrated in a CMOS compatible silicon nitride photonic circuit.