28th Annual Student Research Conference
Improved type I SPDC photon-polarization entanglement using a cw-diode laser
Nathaniel M. Aden
Dr. Michael Goggin, Faculty Mentor
We produce and detect high-quality polarization-entangled photons at low cost using a cw-diode laser. Entangled pairs of photons are produced by type I spontaneous parametric downconversion, obtained by passing 405nm light from a 20mW cw-diode laser through two beta barium borate (BBO) crystals. The spectral spread of a cw-diode laser limits the amount of polarization entanglement achievable for the down converted photon pairs. To overcome this we precompensate the pump beam by passing it through a birefringent quartz crystal before the down conversion crystals to cause a delay between the horizontally polarized and vertically polarized states. By optimizing the thickness of the quartz we are able to increase the tangle of the photons. We will demonstrate the improvement in the tangle of the photons provide details of the equipment and procedures used so that the method can be replicated in other labs.
Keywords: Quantum, Entanglement, Phtotn, Polarization
Topic(s):Physics
Presentation Type: Oral Paper
Session: 414-2
Location: MG 1096
Time: 2:45