# Semiconductor quantum dots as entangled light sources

David Gershoni

*Department of Physics , Technion
*

Entangled photon pairs are emitted from a biexciton decay cascade of
single quantum dots when spectral filtering is applied. We show this by experimentally measuring the density matrix of the polarization state
of the photon pair emitted from a continuously pumped quantum dot. The
matrix clearly satisfies the Peres criterion for entanglement.
By applying in addition a temporal window, the quantum dot becomes an entangled light source.