Photon-Number-Resolving Transition-Edge Sensors for the Metrology of Photonic Microstructures based on Semiconductor Quantum Dots

摘要

Light sources for applications in quantum information, quantum-enhanced sensing and quantum metrology are attractingincreasing scientific interest. To gain inside into the underlying physical processes of quantum light generation, efficientphoton detectors and experimental techniques are required to access the photon statistics. In this work, we employphoton-number-resolving (PNR) detectors based on superconducting transition-edge sensors (TESs) for the metrology ofphotonic microstructures with semiconductor quantum dots (QDs) as emitters. For the PNR analysis, we developed astate of the art PNR detection system based on fiber-coupled superconducting TESs. Our stand-alone system comprisessix tungsten TESs, read out by six 2-stage-SQUID current sensors, and operated in a compact detector unit integratedinto an adiabatic demagnetization refrigerator. This PNR detection system enables us to directly access the photonstatistics of the light field emitted by our photonic microstructures. In this contribution, we focus on the PNR study ofdeterministically fabricated quantum light sources emitting single indistinguishable photons as well as twin-photonstates. Additionally, we present a PNR-analysis of electrically pumped QD micropillar lasers exhibiting a peculiarbimodal behavior. Employing TESs our work provides direct insight into the complex emission characteristics of QDbasedlight sources. We anticipate, that TES-based PNR detectors, will be a viable tool for implementations of photonicquantum information processing relying on multi-photon states.