Interaction-free measurements with superconducting qubits

TL;DR

This paper presents a protocol using superconducting qubits to detect the presence of a current pulse without energy exchange, advancing quantum measurement techniques.

Contribution

It introduces an interaction-free measurement method in superconducting circuits, enabling detection without energy transfer, which is novel in quantum circuit measurement.

Findings

Successful detection of current pulses without energy exchange

Demonstration of interaction-free measurement in superconducting qubits

Potential applications in quantum sensing and information processing

Abstract

An interaction-free measurement protocol is described for a quantum circuit consisting of a superconducting qubit and a read-out Josephson junction. By measuring the state of the qubit one can ascertain the presence of a current pulse through the circuit at a previous time without any energy exchange between the qubit and the pulse.