Adiabatic quantum computation with flux qubits, first experimental results

TL;DR

This paper reports the first experimental results on adiabatic quantum computation using flux qubits, demonstrating multi-qubit system characterization and Hamiltonian reconstruction, advancing practical realization of AQC.

Contribution

It presents the first experimental investigation of multi-flux-qubit systems for adiabatic quantum computation, including characterization and Hamiltonian reconstruction.

Findings

Characterized 2, 3, and 4 flux qubit systems.

Designed two-qubit systems with coupling energies up to several kelvins.

Reconstructed the system's Hamiltonian from measurements.

Abstract

Controllable adiabatic evolution of a multi-qubit system can be used for adiabatic quantum computation (AQC). This evolution ends at a configuration where the Hamiltonian of the system encodes the solution of the problem to be solved. As a first steps towards realization of AQC we have investigated two, three and four flux qubit systems. These systems were characterized by making use of a radio-frequency method. We designed two-qubit systems with coupling energies up to several kelvins. For the three-flux-qubit systems we determined the complete ground-state flux diagram in the three dimensional flux space around the qubits common degeneracy point. We show that the system`s Hamiltonian can be completely reconstructed from our measurements. Our concept for the implementation of AQC, by making use of flux qubits, is discussed.