Low Temperature Physics: 38, 283 (2012); https://doi.org/10.1063/1.3701717 (18 pages)
Физика Низких Температур: Том 38, Выпуск 4 (Апрель 2012), c. 360-381    ( к оглавлению , назад )

Multiphoton transitions in Josephson-junction qubits (Review Article)

S.N. Shevchenko and A.N. Omelyanchouk

B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine 47 Lenin Ave., Kharkov 61103, Ukraine
E-mail: sshevchenko@ilt.kharkov.ua

E. Il'ichev

Institute of Photonic Technology, PO Box 100239, D-7702 Jena, Germany

Received December 30, 2011

Аннотация

Two basic physical models, a two-level system and a harmonic oscillator, are realized on the mesoscopic scale as coupled qubit and resonator. The realistic system includes moreover the electronics for controlling the distance between the qubit energy levels and their populations and to read out the resonator's state, as well as the unavoidable dissipative environment. Such rich system is interesting both for the study of fundamental quantum phenomena on the mesoscopic scale and as a promising system for future electronic devices. We present recent results for the driven superconducting qubit–resonator system, where the resonator can be realized as an LC circuit or a nanomechanical resonator. Most of the results can be described by the semiclassical theory, where a qubit is treated as a quantum two-level system coupled to the classical driving field and the classical resonator. Application of this theory allows to describe many phenomena for the single and two coupled superconducting qubits, among which are the following: the equilibrium-state and weak-driving spectroscopy, Sisyphus damping and amplification, Landau–Zener–Stückelberg interferometry, the multiphoton transitions of both direct and ladder- type character, and creation of the inverse population for lasing.

PACS: 42.50.Hz Strong-field excitation of optical transitions in quantum systems; multiphoton processes; dynamic Stark shift;
PACS: 85.25.Am Superconducting device characterization, design, and modeling;
PACS: 85.25.Hv Superconducting logic elements and memory devices; microelectronic circuits.

Ключевые слова: superconducting qubit, multiphoton excitation, multilevel system, spectroscopy, interferometry.