Optical measurement of double-dot population using photon transmission via three coupled microresonators

Abstract

A scheme for measuring the state of a charge qubit on a semiconductor single-electron double quantum dot (DQD) coupled to a photonic molecule (PM) consisting of three optical microresonators is proposed. The DQD that is the qubit plays the role of a nonlinear element whose electron state affects a PM response to an external laser field. Analysis of the spectroscopic response of the structure in the steady-state regime allows one to determine the state of the qubit. As an example, the spectrum of the PM formed by three GaAs microdisk resonators are calculated. The effect of various system parameters on the measuring contrast and the signal-to-noise ratio is studied. It is shown that this ratio can reach values of 15 000–20 000 for certain sets of parameters.

Control of photon transport in an optical structure of four microresonators using spectral engineering

“…In our work, we consider a T-shaped nanophotonic structure formed from four single-mode microresonators (MRs), which are interconnected by photon tunneling [8,9]. Three MRs form a one-dimensional transport system, in which the first and third MRs (hereinafter, MR 1 and MR 3) are the input and output ports (source and sink) for the external laser field, and the central MR (hereinafter, MR 2) plays the role of a base.…”