Optical spintronics in solids for quantum information processing

Kai-Mei Fu
HP Labs

The optical detection and control of solid-state spins has important applications in the field of quantum information. Not only is all-optical spin control useful for spin-based single-qubit operations, it can also be used to measure the fundamental relaxation times of spin systems. This knowledge is useful for determining the potential a spin system will have as a qubit in a quantum information application. In the first part of my talk I will present experiments which measure population relaxation T₁, inhomogeneous dephasing T₂*, and homogeneous dephasing T₂ of electrons bound to donors in GaAs.

Optics also can provide a communication link between distant spin qubits for two-qubit interactions and quantum communication. In the second part of my talk I will discuss our effort at HP Labs to couple nitrogen-vacancy centers in diamond to on-chip photonic devices in order to realize quantum information networks.