Résumé
Fast and efficient single-photon detectors are of paramount importance for a broad range of applications, e.g. in optical quantum information technologies. A variety of novel and refined photon counting devices has resulted from the need of ever better performance. One such device is the resonant tunneling diode (RTD) single-photon detector. Compared to conventional single-photon detectors, RTDs provide several advantageous characteristics. Since in RTDs a tunneling current is gated by photogenerated charge carriers, they are inherently photon-number resolving, and the RTD currentvoltage characteristic’s negative differential conductance region allows for higher functionality, e.g. the operation as an optically triggered bistable switch. Here, we present an overview on RTD single-photon detectors with a focus on the stateof- the-art, its underlying physical mechanisms as well the device limitations, and recent developments. We compare different RTD device geometries and operation schemes for enhanced detection efficiencies and operation frequencies.