Ville Maisi

Division of Solid State Physics, Lund University

Detecting single electrons and microwave photons with semiconductor quantum dots

Building a detector capable to resolve individual microwave photons has attained a strong focus in recent years. Approaches based on superconducting qubits have reached single photon resolution with high quantum efficiency. However, these detectors operate non-continuously, thus requiring precise pulsing and considerations about the timing to perform the detection optimally. I present our efforts to build a microwave photodetector based on counting electron tunnelling events in a double quantum dot photon absorber. This detector operates continuously avoiding the pulsing and thus responds to the input photons as they arrive. In addition to these technological developments, I'll discuss the relevant physics effects taking place in these detectors such as hybridization of the quantum states and the coherence under continuous charge readout.