Data Center Quantum Networks: From Experiment to System*

Scaling up quantum computers will require interconnecting small quantum computer nodes into larger multicomputer systems that can collaborate to solve large problems.  This scaling requires fast, robust, high-fidelity creation of inter-node entanglement.  Brilliant experiments have shown that the basic technology works; the next stage in evolution is to move from experiment to system.

Progressing to system requires solving many classic (but not always classical) computer engineering problems: efficient design of photonic switching networks,  fair and reliable allocation of resources, distributed control, tolerance of both errors and hardware failures, interoperability of heterogeneous technologies built by different organizations, and compilation of application programs for execution on multicomputers.

I will present our testbed network, which begins with spontaneous parametric down conversion (SPDC) entanglement sources and switched photon measurement nodes and will eventually include nodes with memory and ultimately connect full quantum computers.  Our approach includes open access to specifications and source code for the interconnect protocols, with the long-term goal of influencing standards for quantum networking equipment.