Landau-Zener-Stuckelberg interferometry

TL;DR

Landau-Zener-Stuckelberg interferometry involves quantum interference effects in driven two-level systems, with recent experiments demonstrating its potential for characterizing and controlling superconducting qubits.

Contribution

This paper reviews recent experimental results and theory on LZS interferometry in superconducting qubits, highlighting its applications in system characterization and control.

Findings

LZS interferometry reveals interference patterns in driven TLSs.

Experimental techniques enable parameter extraction of qubits.

Strong driving allows for fast quantum control.

Abstract

A transition between energy levels at an avoided crossing is known as a Landau-Zener transition. When a two-level system (TLS) is subject to periodic driving with sufficiently large amplitude, a sequence of transitions occurs. The phase accumulated between transitions (commonly known as the Stuckelberg phase) may result in constructive or destructive interference. Accordingly, the physical observables of the system exhibit periodic dependence on the various system parameters. This phenomenon is often referred to as Landau-Zener-Stuckelberg (LZS) interferometry. Phenomena related to LZS interferometry occur in a variety of physical systems. In particular, recent experiments on LZS interferometry in superconducting TLSs (qubits) have demonstrated the potential for using this kind of interferometry as an effective tool for obtaining the parameters characterizing the TLS as well as its interaction with the control fields and with the environment. Furthermore, strong driving could allow for fast and reliable control of the quantum system. Here we review recent experimental results on LZS interferometry, and we present related theory.