Spatial and temporal characteristics of spontaneous parametric down-conversion with varying focal planes of interacting beams
arXiv:2212.12571 · doi:10.1140/epjd/s10053-023-00754-x
Abstract
Spontaneous parametric down-conversion (SPDC) is a widely used process to prepare entangled photon pairs. In SPDC, a second-order nonlinear crystal is pumped by a coherent laser beam to generate photon pairs. The photon pairs are usually detected by single-mode fibers (SMF), where only photons in a Gaussian mode can be collected. The collection modes possess typical Gaussian parameters, namely a beam waist and a focal plane position. The collection efficiency of photons highly depends on the choice of both parameters. The exact focal plane position of the pump beam relative to those of the detection modes is difficult to determine in a real experiment. Usually, theoretical and experimental studies assume that the focal plane positions of the pump and the generated beams are positioned in the center of the crystal. The displacement of beam focal planes can lead to deviations from expected results and the coupling efficiency into SMF can increase or decrease. In this work, we consider variable positions of focal planes and investigate how shifts of these focal planes influence the spatial and temporal properties of photon pairs. We present SPDC arrangements, in which the knowledge of the exact position of the focal planes is essential, as well as scenarios, where focal plane displacements do not contribute significantly to experimental outcomes. These findings are of particular interest for achieving higher efficiency in SPDC experiments.
10 pages, 5 figures
References in corpus (34)
- Entanglement of Orbital Angular Momentum States of Photons
- Quantum computational advantage using photons
- Quantum Entanglement of High Angular Momenta
- Photonic quantum information processing: a concise review
- Laguerre-Gaussian mode sorter
- Imaging with quantum states of light
- Spatial correlations in parametric down-conversion
- Entanglement Certification From Theory to Experiment
- Chip-based photon quantum state sources using nonlinear optics
- Generation and Confirmation of a (100x100)-dimensional entangled Quantum System
- Programmable unitary spatial modes manipulation
- A Quantum Pulse Gate based on Spectrally Engineered Sum Frequency Generation
- Orbital angular momentum of photons and the entanglement of Laguerre-Gaussian modes
- Entangled Photon-Pair Sources based on three-wave mixing in bulk crystals
- Optimal Co-linear Gaussian Beams for Spontaneous Parametric Down-Conversion
- Full characterisation of the quantum spiral bandwidth of entangled biphotons
- Shaping the waveform of entangled photons
- Measuring azimuthal and radial modes of photons
- Effective fiber-coupling of entangled photons for quantum communication
- A high-brightness source of polarization-entangled photons optimized for applications in free space
- Shaping the joint spectrum of down-converted photons through optimized custom poling
- Passively stable distribution of polarisation entanglement over 192 km of deployed optical fibre
- Quantum state engineering with twisted photons via adaptive shaping of the pump beam
- Spectral decomposition of entangled photons with an arbitrary pump
- Pure down-conversion photons through sub-coherence length domain engineering
- Dimensionality of the spatio-temporal entanglement of PDC photon pairs
- Schmidt modes generated in parametric downconversion
- High efficiency coupling of photon pairs in practice
- Spatiotemporal correlations in entangled photons generated by spontaneous parametric down conversion
- Effects of crystal length on the angular spectrum of spontaneous parametric downconversion photon pairs
- Experimental Study of the Generalized Jarzysnki's Fluctuation Relation Using Entangled Photons
- Generalized description of the spatio-temporal biphoton State in spontaneous parametric down-conversion
- Klyshko's Advanced-Wave Picture in Stimulated Parametric Down-Conversion with a Spatially Structured Pump Beam
- Where are photons created in parametric down conversion? On the control of the spatio-temporal properties of biphoton states