Spectrally uncorrelated biphotons generated from “the family of BBO crystal”

Abstract

Summary Spectrally intrinsically uncorrelated biphoton states generated from nonlinear crystals are very important but rare resources for quantum photonics and quantum information applications. Previously, such biphoton states were generated from several kinds of crystals, however, their wavelength ranges and nonlinear efficiencies were still limited for various applications. In order to explore new crystal for wider wavelength range and higher nonlinear efficiency, here we theoretically study the generation of spectrally uncorrelated biphoton states from 14 crystals in the “BBO family,” including BBO, CLBO, KABO, KBBF, RBBF, CBBF, BABF, BiBO, LBO, CBO, LRB4, LCB, YCOB, and GdCOB. They satisfy three kinds of group‐velocity matching condition from near‐infrared to telecom wavelengths. Furthermore, heralded single photons can be generated with a purity as high as 0.98, which is achieved without any narrow filtering. The indistinguishability of photons from independent sources is examined by the Hong‐Ou‐Mandel interference, which results in a visibility of 98% also without any further filtering, that is, photons from different heralded single‐photon sources are highly indistinguishable. Our study may provide single‐photon sources with good performance for quantum information processing at near‐infrared and telecom wavelengths.

An Optimal Polarization-Entanglement Source: Frequency-Converted SPDC with Degeneracy, Indistinguishability, and Ultra-High Purity Configurable Over a Large Spectral Range

“…In Refs. [41][42][43] the authors locate these states in the isomorphs of KTP, KDP, and BBO, adding to the list of wavelengths at which these states can be obtained. However, there is still a broad range of degeneracy wavelengths that cannot be achieved, and thus there is a trade-off; one must sacrifice high purity for the sake of degeneracy and indistinguishability, or one must sacrifice degeneracy and indistinguishability for the sake of high purity.…”

Mid-infrared spectrally-uncorrelated biphotons generation from doped PPLN: a theoretical investigation

“…However, the three GVM conditions listed in Eqs. (8)(9)(10) with the degenerated wavelengths are the most widely used cases in the experiments [40][41][42]. Especially, the GVM 3 condition has a symmetric distribution along the anti-diagonal direction, i.e., f (ω s , ω i ) = f (ω i , ω s ), which is the prerequisite condition for high-visibility HOM interferences.…”

Counter-propagating spectrally uncorrelated biphotons at 1550 nm generated from periodically poled MTiOXO4 (M = K, Rb, Cs; X = P, As)

“…Here we make a simulation of such a HOM interference for PPRTP under type-0 and type-II phase-matching conditions. The simulation is performed with the following equation [41][42][43]:…”