Patent ID: 7791052

Claim:
A method of generating a single photon, comprising: preparing an optical resonator including a resonator mode of a resonance angular frequency ω c ; preparing a material contained in the optical resonator, including a low energy state |g> and a high energy state |e>, and including a transition angular frequency ω a between |g>−|e> that is varied by an external field; applying, to the material, light of an angular frequency ω l different from the resonance angular frequency ω c ; and applying a first external field to the material to vary the transition angular frequency ω a to resonate with the angular frequency ω l , such that a state of the material is changed to the high energy state |e>, and then applying a second external field to the material to vary the transition angular frequency ω a to resonate with the resonance angular frequency ω c , such that the state of the material is restored to the low energy state |g>.