Temperature Dependence of the Single-Photon Sensitivity of a Quantum Dot, Optically Gated, Field-Effect Transistor

The potential advantages that quantum communications and computing have over their conventional counterparts have seeded a growing interest in transmitting and processing information with individual photons. However, if these technologies are ever to reach their full potential, improved single-photon detectors will have to be developed. Here, I present a systematic study of the temperature dependence of the electrical noise in a quantum dot, optically gated, field-effect transistor (QDOGFET) and detail how the noise influences the sensitivity of this novel single-photon detector. Previous studies have shown that when cooled to 4K, QDOGFET's exhibit single-photon sensitivity and photon-number resolving capabilities; however, there has been no systematic study of how operating temperature affects their performance. Here, we measure the noise spectra of a device for a range of sample temperatures between 7K and 60K. We use the noise data to determine the signal-to-noise ratio of the optical response of the device for various temperatures and detection rates. Our analysis indicates that QDOGFET's can operate over a broad range of temperatures, where increased operating temperature can be traded for decreased sensitivity.