Experimental demonstration of work fluctuations along a shortcut to adiabaticity with a superconducting Xmon qubit

TL;DR

This paper experimentally measures work fluctuations in a superconducting qubit during a shortcut-to-adiabaticity process, confirming theoretical predictions about work cost and quantum geometry effects.

Contribution

It provides the first experimental verification of work fluctuation properties in STA protocols using superconducting qubits, based on recent theoretical developments.

Findings

Average STA work is conserved.

STA excess work fluctuations equal the quantum geometric tensor.

Experimental techniques accurately measure work distribution.

Abstract

In a `shortcut-to-adiabaticity' (STA) protocol, the counter-diabatic Hamiltonian, which suppresses the non-adiabatic transition of a reference `adiabatic' trajectory, induces a quantum uncertainty of the work cost in the framework of quantum thermodynamics. Following a theory derived recently [Funo et al 2017 Phys. Rev. Lett. 118 100602], we perform an experimental measurement of the STA work statistics in a high-quality superconducting Xmon qubit. Through the frozen-Hamiltonian and frozen-population techniques, we experimentally realize the two-point measurement of the work distribution for given initial eigenstates. Our experimental statistics verify (i) the conservation of the average STA work and (ii) the equality between the STA excess of work fluctuations and the quantum geometric tensor.