Ti/Au TES AS SUPERCONDUCTING DETECTOR FOR QUANTUM TECHNOLOGIES

Single photon detectors are fundamental tools for quantum metrology, e. g. to calibrate both detectors and sources, as for quantum information. One of the most promising detectors able to resolve single photons is the transition-edge sensor (TES). We report our last results obtained with Ti/Au TES deposited on SiN substrate. Photon counting measurements, obtained by using pulsed sources, in the NIR-visible wavelength range, show the ability to resolve up to fourteen photons with an energy resolution of 0.44 eV at 690 nm (1.80 eV) and 0.38 eV at 1310 nm (0.95 eV), with a good linearity. A preliminary measurement obtained by using a parametric down conversion (PDC) heralded single photon source, at 812 nm (1.53 eV), is also reported.