The laboratory features:
• A cryogenic system of 8 superconducting single-photon detectors with high quantum efficiency QE > 85%, low noise (<100 Hz) and 35 ps temporal resolution. The system is equipped with 8-channel high-speed electronics (1 ps temporal resolution) for time correlation measurements of single photons in the telecom and visible spectral region.
• 4 fully equiped optical tables for integrated quantum optical measurements, including ultra-stble 5-axes nanopositiones for on/off chip optical coupling by means of “end-fire” or integrated grating couplers. Typical experiments include: generation of entangled photon pairs by spontaneous parametric down-conversion and four-wave-mixing; high-resolution measurement of the quantum state joint spectral density; heralded single photon measurements; Franson interferometry for entanglement assessment.
• A cryogenic system for high spatial and spectral resolution microscopy measurements, featuring ultra-low vibrations and working between 3.2 and 300 K in the visible-NIR spectral region. The system can be used for quantum optical experiments involving single-photon emission by semiconductor quantum dots or diamond NV centers. The system can also be used for the study of single-photon detectors based on superconducting materials deposited on top of integrated photonic circuits.
• Other relevant equipment at the Quantum Photonics Laboratory are: Several high-resolution tunable infrared lasers int he telecom range; a high peak power femtosecond fiber-laser at 1.5 um wavelength; two high resolution grating spectrometers equipped with InGaAs array detectors; a radiofrequency generator up to 25 GHz; several fiber-coupled electro-optical modulators and drivers.
Responsible: Matteo Galli