Time-resolved purification of photon pairs from ultrasmall sources
arXiv:2307.04855 · doi:10.1021/acsphotonics.3c01169
Abstract
Generation of entangled photons through spontaneous parametric down-conversion (SPDC) from ultrasmall sources like thin films, metasurfaces, or nanoantennas, offers unprecedented freedom in quantum state engineering. However, as the source of SPDC gets smaller, the role of photoluminescence increases, which leads to the contamination of two-photon states with thermal background. Here we propose and implement a solution to this problem: by using pulsed SPDC and time distillation, we increase the purity and the heralding efficiency of the photon pairs. In the experiment, we increase the purity of two-photon states generated in a 7 m film of lithium niobate from 0.002 to 0.99. With the higher purity, we were able to observe and characterize different polarization states of photon pairs generated simultaneously due to relaxed phase matching. In particular, we showed the presence of orthogonally polarized photons, potentially usable for the generation of polarization entanglement.
References in corpus (18)
- Ultra-bright source of polarization-entangled photons
- Experimental Boson Sampling
- Metasurfaces for Quantum Photonics
- Resonant Semiconductor Metasurfaces for Generating Complex Quantum States
- Ultrathin quantum light source enabled by a nonlinear van der Waals crystal with vanishing interlayer-electronic-coupling
- Overcoming Noise in Entanglement Distribution
- Spatially entangled photon-pairs from lithium niobate nonlocal metasurfaces
- Simple and efficient quantum key distribution with parametric down-conversion
- Spontaneous photon-pair generation at the nanoscale
- Microscale generation of entangled photons without momentum conservation
- Introduction to the Absolute Brightness and Number Statistics in Spontaneous Parametric Down-Conversion
- Is high-dimensional photonic entanglement robust to noise?
- Dynamics of the non-classical light from a single solid-state quantum emitter
- Efficient single-photon pair generation by spontaneous parametric down-conversion in nonlinear plasmonic metasurfaces
- A dimensionality and purity measure for high-dimensional entangled states
- Idealised EPR states from non-phase matched parametric down conversion
- Purification of single photons by temporal heralding of quantum dot sources
- Luminescence-induced noise in single photon sources based on BBO crystals