Engineering silicon-based photonic crystal cavities for NV-center quantum information processing

Silicon slab photonic crystal micro cavities designed for of-resonant coupling to nitrogen vacancy (NV) centers were simulated and fabricated. FDTD-simulations show the partial density of states spectrally near the NV-center electric dipole transition can be tuned to reduce decoherence of an excited NV-center despite this transition being above the silicon electronic band gap. The partial density of states at the NV-center transition can be made to dip below half of the free-space partial density of states without significantly affecting the cavity mode quality factor. These promising results sustain the merits of using silicon as a base photonic crystal material for quantum information processing even when integrated emitters radiate above the electronic band gap of silicon.