Synchronization and bistability of a qubit coupled to a driven dissipative oscillator.

We study numerically the behavior of a qubit coupled to a quantum dissipative driven oscillator (resonator). Above a critical coupling strength the qubit rotations become synchronized with the oscillator phase. In the synchronized regime, at certain parameters, the qubit exhibits tunneling between two orientations with a macroscopic change of the number of photons in the resonator. The lifetimes in these metastable states can be enormously large. The synchronization leads to a drastic change of qubit radiation spectrum with the appearance of narrow lines corresponding to recently observed single artificial-atom lasing [O. Astafiev, Nature (London) 449, 588 (2007)].

[1]  Todd A. Brun,et al.  A simple model of quantum trajectories , 2002 .

[2]  Ian C. Percival,et al.  Quantum state diffusion, localization and quantum dispersion entropy , 1993 .

[3]  R. Graham,et al.  Two-state system coupled to a boson mode: Quantum dynamics and classical approximations , 1984 .

[4]  Graham,et al.  Statistical spectral and dynamical properties of two-level systems. , 1986, Physical review letters.

[5]  H J Mamin,et al.  Feedback cooling of a cantilever's fundamental mode below 5 mK. , 2007, Physical review letters.

[6]  Kus Statistical properties of the spectrum of the two-level system. , 1985, Physical review letters.

[7]  Jürgen Kurths,et al.  Synchronization: Phase locking and frequency entrainment , 2001 .

[8]  J. Eberly,et al.  Theory of Spontaneous-Emission Line Shape in an Ideal Cavity , 1983 .

[9]  F Balestro,et al.  Coherent oscillations in a superconducting multilevel quantum system. , 2004, Physical review letters.

[10]  A. N. Korotkov,et al.  Continuous weak measurement of quantum coherent oscillations , 2001 .

[11]  A. Messiah Quantum Mechanics , 1961 .

[12]  E. Jaynes,et al.  Comparison of quantum and semiclassical radiation theories with application to the beam maser , 1962 .

[13]  Dissipative quantum chaos: transition from wave packet collapse to explosion. , 2005, Physical review letters.

[14]  M. S. Zubairy,et al.  Quantum optics: Frontmatter , 1997 .

[15]  P. Joyez,et al.  Manipulating the Quantum State of an Electrical Circuit , 2002, Science.

[16]  E Il'ichev,et al.  Continuous monitoring of Rabi oscillations in a Josephson flux qubit. , 2003, Physical review letters.

[17]  A N Cleland,et al.  Superconducting qubit storage and entanglement with nanomechanical resonators. , 2004, Physical review letters.

[18]  A. Korotkov Continuous quantum measurement of a double dot , 1999, cond-mat/9909039.

[19]  S. Girvin,et al.  Strong coupling of a single photon to a superconducting qubit using circuit quantum electrodynamics , 2004, Nature.

[20]  A. Perelomov Generalized Coherent States and Their Applications , 1986 .

[21]  Jürgen Kurths,et al.  Synchronization - A Universal Concept in Nonlinear Sciences , 2001, Cambridge Nonlinear Science Series.

[22]  L Frunzio,et al.  Generating single microwave photons in a circuit. , 2007, Nature.

[23]  P. Milonni,et al.  Chaos in quantum optics , 1985 .

[24]  N. Gisin,et al.  The quantum state diffusion picture of physical processes , 1993 .

[25]  N. Gisin,et al.  The quantum-state diffusion model applied to open systems , 1992 .

[26]  Yu. A. Pashkin,et al.  Single artificial-atom lasing , 2007, Nature.

[27]  O. V. Zhirov,et al.  Quantum synchronization , 2006 .

[28]  Quantum chaos in open systems: a quantum state diffusion analysis , 1995, quant-ph/9509015.

[29]  Nonideal quantum detectors in Bayesian formalism , 2002, cond-mat/0211647.