Motivated by recent interest in implementing circuit quantum electrodynamics with semiconducting quantum dots, we consider a double quantum dot (DQD) capacitively coupled to a superconducting resonator that is driven by the microwave field of a superconducting transmission line. We analyze the DQD current response using input-output theory and show that the resonator-coupled DQD is a sensitive microwave single photon detector. Using currently available experimental parameters of DQD-resonator coupling and dissipation, including the effects of 1/f charge noise and phonon noise, we determine the parameter regime for which incident photons are completely absorbed and near unit ≳ 98\% efficiency can be achieved. We show that this regime can be reached by using very high quality resonators with quality factor Q≃105.
@article{arxiv.1512.06939,
title = {Quantum efficiency of a microwave photon detector based on a double quantum dot},
author = {Clement H. Wong and Maxim G. Vavilov},
journal= {arXiv preprint arXiv:1512.06939},
year = {2017}
}