Cavity-Mediated Entanglement Generation Via Landau-Zener Interferometry

C. M. Quintana, K. D. Petersson, L. W. McFaul, S. J. Srinivasan, A. A. Houck, and J. R. Petta

Phys. Rev. Lett. 110, 173603 – Published 26 April 2013

Abstract

We demonstrate quantum control and entanglement generation using a Landau-Zener beam splitter formed by coupling two transmon qubits to a superconducting cavity. Single passage through the cavity-mediated qubit-qubit avoided crossing provides a direct test of the Landau-Zener transition formula. Consecutive sweeps result in Landau-Zener-Stückelberg interference patterns, with a visibility that can be sensitively tuned by adjusting the level velocity through both the nonadiabatic and adiabatic regimes. Two-qubit state tomography indicates that a Bell state can be generated via a single passage, with a fidelity of 78% limited by qubit relaxation.

Received 4 December 2012

DOI:https://doi.org/10.1103/PhysRevLett.110.173603

Authors & Affiliations

C. M. Quintana¹, K. D. Petersson¹, L. W. McFaul¹, S. J. Srinivasan², A. A. Houck², and J. R. Petta^1,3

¹Department of Physics, Princeton University, Princeton, New Jersey 08544, USA
²Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA
³Princeton Institute for the Science and Technology of Materials (PRISM), Princeton University, Princeton, New Jersey 08544, USA