Source Of Polarization-entangled Photon Pairs Research Articles

Compact source of polarization-entangled photon pairs

We present a compact source of polarization-entangled photon pairs at a wavelength of 805 nm using a violet single-mode laser diode as the pump source of type-II spontaneous parametric down-conversion. The source exhibits entanglement and pair-rate comparable to conventional systems utilizing large frame ion lasers thus significantly increases the practicality of novel quantum information or quantum metrology applications.

Compact all-solid-state source of polarization-entangled photon pairs

A compact source of polarization-entangled photon pairs at a wavelength of 856 nm is realized using a frequency-doubled laser diode as the pump source for cavity-enhanced type-II spontaneous parametric down-conversion. Our setup generates photon pairs with entanglement visibility of ⩾95% and with count rates comparable to those of standard experiments based on large-frame ion lasers.

Ultrabright source of polarization-entangled photons

Using the process of spontaneous parametric down conversion in a novel two-crystal geometry, one can generate a source of polarization-entangled photon pairs which is orders of magnitude brighter than previous sources. We have measured a high level of entanglement between photons emitted over a relatively large collection angle, and over a 10-nm bandwidth. As a demonstration of the source intensity, we obtained a 242-$\sigma$ violation of Bell's inequalities in less than three minutes.

New high-intensity source of polarization-entangled photon pairs.

We report on a high-intensity source of polarization-entangled photon pairs with high momentum definition. Type-II noncollinear phase matching in parametric down conversion produces true entanglement: No part of the wave function must be discarded, in contrast to previous schemes. With two-photon fringe visibilities in excess of 97%, we demonstrated a violation of Bell's inequality by over 100 standard deviations in less than 5 min. The new source allowed ready preparation of all four of the EPR-Bell states.