Polarized electrons in a low-energy spin-transparent storage ring as a quantum computer

Electrons in spin-transparent storage rings can exhibit a spin-coherence time of several hours, presenting a compelling platform for quantum computing. Spin-polarized electrons are generated by shining circularly-polarized light onto a photocathode, and then injected into the storage ring. Then, single-qubit rotations can be implemented by a pulsed solenoid, and readout of the spin is done using a Mott polarimeter. However, a significant question of the viability of storage rings as a quantum computing platform remains: to date, there is no demonstration of a two-qubit gate. In this talk, I will explore the possibility of using an entangled train of light pulses impinging on a photocathode to produce electrons with entangled spins. These spin-entangled electrons could then be used as a resource in a measurement-based scheme to perform multi-qubit gates in the storage ring.