  We present two novel schemes to generate photon polarization entanglement via
single electron spins confined in charged quantum dots inside microcavities.
One scheme is via entangled remote electron spins followed by
negatively-charged exciton emissions, and another scheme is via a single
electron spin followed by the spin state measurement. Both schemes are based on
giant circular birefringence and giant Faraday rotation induced by a single
electron spin in a microcavity. Our schemes are deterministic and can generate
an arbitrary amount of multi-photon entanglement. Following similar procedures,
a scheme for a photon-spin quantum interface is proposed.
