Simulating a Topological Transition in a Superconducting Phase Qubit by Fast Adiabatic Trajectories

Abstract

The significance of topological phases has been widely recognized in the community of condensed matter physics. The well controllable quantum systems provide an artificial platform to probe and engineer various topological phases. The adiabatic trajectory of a quantum state describes the change of the bulk Bloch eigenstates with the momentum, and this adiabatic simulation method is however practically limited due to quantum dissipation. Here we apply the `shortcut to adiabaticity' (STA) protocol to realize fast adiabatic evolutions in the system of a superconducting phase qubit. The resulting fast adiabatic trajectories illustrate the change of the bulk Bloch eigenstates in the Su-Schrieffer-Heeger (SSH) model. A sharp transition is experimentally determined for the topological invariant of a winding number. Our experiment helps identify the topological Chern number of a two-dimensional toy model, suggesting the applicability of the fast adiabatic simulation method for topological systems.

37 pages, 8 figures including Supplementary

References in corpus (8)

• Measuring the Chern number of Hofstadter bands with ultracold bosonic atoms
• Simple pulses for elimination of leakage in weakly nonlinear qubits
• Topological Quantum Matter with Ultracold Gases in Optical Lattices
• Shortcut to adiabatic passage in two and three level atoms
• Analytic control methods for high fidelity unitary operations in a weakly nonlinear oscillator
• An Aharonov-Bohm interferometer for determining Bloch band topology
• Observation of topological transitions in interacting quantum circuits
• Measuring a topological transition in an artificial spin 1/2 system