RESUMO
The design and implementation of a novel source of degenerate polarization entangled photon pairs in the telecom band, based on a cavity enhanced parametric downconversion process, is presented. Two of the four maximally entangled Bell states are produced; the remaining two are obtainable by the addition of a half wave plate into the setup. The coincident photon detection rate in the A/D basis between two detectors at the output of the device revealed the production of highly entangled states, resulting in quantum interference visibilities of 0.971 ± 0.041 (Ï = 0 state) and 0.932 ± 0.036 (Ï = π state) respectively. The entangled states were found to break the Clauser-Horne-Shimony-Holt (CHSH) Bell inequality by around 6 standard deviations. From the measured coincidence counting rates and the optical system losses, an entangled photon pair production rate of 8.9 × 10(4) s(-1) mW(-1) pump was estimated.
Assuntos
Amplificadores Eletrônicos , Lasers de Estado Sólido , Telecomunicações/instrumentação , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Modelos Teóricos , FótonsRESUMO
Two major requirements in the construction of the Hong-Ou-Mandel interferometer are the alignment and length balancing of two optical paths. A new method is presented for meeting these requirements that requires no custom optics or expensive equipment. Using this method, a two photon interferometer sourced by degenerate noncollinear parametric photon pairs was aligned and the optical paths were balanced to within an average of 11.6 microm, yielding two-photon interference features with visibilities of approximately 0.9. The method is applicable to arbitrary noncollinear emission angles, including nondegenerate downconversion situations where the signal and idler emission angles differ.
