Frequency Division Multiplexing Readout and Simultaneous Manipulation of an Array of Flux Qubits

TL;DR

This paper demonstrates a scalable frequency division multiplexing readout scheme for superconducting flux qubits, enabling simultaneous measurement and control of multiple qubits with a single microwave line, significantly advancing quantum circuit scalability.

Contribution

Introduces a frequency division multiplexing technique for superconducting flux qubits allowing parallel readout and manipulation, scalable to hundreds of qubits.

Findings

Successfully read out 6 flux qubits simultaneously.

Achieved time-resolved measurement of 3 qubits.

Discussed scalability to hundreds of qubits.

Abstract

An important desired ingredient of superconducting quantum circuits is a readout scheme whose complexity does not increase with the number of qubits involved in the measurement. Here, we present a readout scheme employing a single microwave line, which enables simultaneous readout of multiple qubits. Consequently, scaling up superconducting qubit circuits is no longer limited by the readout apparatus. Parallel readout of 6 flux qubits using a frequency division multiplexing technique is demonstrated, as well as simultaneous manipulation and time resolved measurement of 3 qubits. We discuss how this technique can be scaled up to read out hundreds of qubits on a chip.