Entanglement transfer from electrons to photons in quantum dots: an open quantumsystem approach

Abstract

We investigate entanglement transfer from a system of two spin-entangled electron–holepairs, each placed in a separate single mode cavity, to the photons emitted due to cavityleakage. Dipole selection rules and a splitting between the light hole and the heavy holesubbands are the crucial ingredients establishing a one-to-one correspondence betweenelectron spins and circular photon polarizations. To account for the measurement of thephotons as well as dephasing effects, we choose a stochastic Schrödinger equation and aconditional master equation approach, respectively. The influence of interactions with theenvironment as well as asymmetries in the coherent couplings on the photon entanglementis analysed for two concrete measurement schemes. The first one is designed to violate theClauser–Horne–Shimony–Holt (CHSH) inequality, while the second one employs thevisibility of interference fringes to prove the entanglement of the photons. Because of thespatial separation of the entangled electronic system over two quantum dots, asuccessful verification of entangled photons emitted by this system would imply thedetection of nonlocal spin entanglement of massive particles in a solid state structure.