Toward flying qubit spectroscopy

TL;DR

This paper proposes a method for spectroscopy of flying qubits using high-frequency AC voltage drive and predicts the power-frequency response, enabling direct measurement of their characteristic frequencies.

Contribution

It introduces a simple setup for flying qubit spectroscopy and combines multiple theoretical approaches and models to predict the device's response.

Findings

Power-frequency map of the multi-terminal device predicted.

Spectroscopy enables direct measurement of flying qubit frequencies.

Validation of quantum manipulations through this method is possible.

Abstract

While the coherent control of two level quantum systems ---qubits--- is now standard, their continuum electronic equivalents ---flying qubits--- are much less developed. A first step in this direction has been achieved in DC interferometry experiments. Here, we propose a simple setup to perform the second step, the spectroscopy of these flying qubits, by measuring the DC response to a high frequency AC voltage drive. Using two different concurring approaches --- Floquet theory and time-dependent simulations --- and three different models --- an analytical model, a simple microscopic model and a realistic microscopic model --- we predict the power-frequency map of the multi-terminal device. We argue that this spectroscopy provides a direct measurement of the flying qubit characteristic frequencies and a key validation for more advanced quantum manipulations.