Synchronization and bistability of qubit coupled to a driven dissipative oscillator (2007)
Zhirov, O. V., Shepelyansky, D. L.
We study numerically the behavior of qubit coupled to a quantum dissipative driven oscillator (resonator). Above a critical coupling strength the qubit rotations become synchronized with the...
Zhirov, O. V., Casati, G., Shepelyansky, D. L.
We study analytically and numerically the one-dimensional quantum Frenkel-Kontorova chain in the regime when the classical model is located in the pinned phase characterized by the gaped phonon...
Fractal Spin Glass Properties of Low Energy Configurations in the Frenkel-Kontorova chain (2007)
Zhirov, O. V., Casati, G., Shepelyansky, D. L.
We study numerically and analytically the classical one-dimensional Frenkel-Kontorova chain in the regime of pinned phase characterized by phonon gap. Our results show the existence of exponentially...
Effects of decoherence and imperfections for quantum algorithms (2007)
Pomeransky, A. A., Zhirov, O. V., Shepelyansky, D. L.
We study effects of static inter-qubit interactions and random errors in quantum gates on the stability of various quantum algorithms including the Grover quantum search algorithm and the quantum...
Frenkel-Kontorova model with cold trapped ions (2007)
Garcia-Mata, I., Zhirov, O. V., Shepelyansky, D. L.
We study analytically and numerically the properties of one-dimensional chain of cold ions placed in a periodic potential of optical lattice and global harmonic potential of a trap. In close...
Dissipative decoherence in the Grover algorithm (2007)
Zhirov, O. V., Shepelyansky, D. L.
Using the methods of quantum trajectories we study effects of dissipative decoherence on the accuracy of the Grover quantum search algorithm. The dependence on the number of qubits and dissipation...
Quantum synchronization (2007)
Zhirov, O. V., Shepelyansky, D. L.
Using the methods of quantum trajectories we study numerically the phenomenon of quantum synchronization in a quantum dissipative system with periodic driving. Our results show that at small values...
Phase diagram for the Grover algorithm with static imperfections (2007)
Pomeransky, A. A., Zhirov, O. V., Shepelyansky, D. L.
We study effects of static inter-qubit interactions on the stability of the Grover quantum search algorithm. Our numerical and analytical results show existence of regular and chaotic phases...
Zhirov, O. V., Casati, G., Shepelyansky, D. L.
We study numerically phonon modes of the classical one-dimensional Frenkel-Kontorova chain, in the regime of pinned phase characterized by the phonon gap and devil's staircase, as well as by a large...
Effects of decoherence and imperfections for quantum algorithms (2007)
Pomeransky, A. A., Zhirov, O. V., Shepelyansky, D. L.
We study effects of static inter-qubit interactions and random errors in quantum gates on the stability of various quantum algorithms including the Grover quantum search algorithm and the quantum...
Frenkel-Kontorova model with cold trapped ions (2006)
Garcia-Mata, I., Zhirov, O. V., Shepelyansky, D. L.
We study analytically and numerically the properties of one-dimensional chain of cold ions placed in a periodic potential of optical lattice and global harmonic potential of a trap. In close...
Dissipative decoherence in the Grover algorithm (2005)
Zhirov, O. V., Shepelyansky, D. L.
Using the methods of quantum trajectories we study effects of dissipative decoherence on the accuracy of the Grover quantum search algorithm. The dependence on the number of qubits and dissipation...
Quantum synchronization (2005)
Zhirov, O. V., Shepelyansky, D. L.
Using the methods of quantum trajectories we study numerically the phenomenon of quantum synchronization in a quantum dissipative system with periodic driving. Our results show that at small values...
Zhirov, O. V., Casati, G., Shepelyansky, D. L.
We study numerically phonon modes of the classical one-dimensional Frenkel-Kontorova chain, in the regime of pinned phase characterized by the phonon gap and devil's staircase, as well as by a large...
Effects of decoherence and imperfections for quantum algorithms (2004)
Pomeransky, A. A., Zhirov, O. V., Shepelyansky, D. L.
We study effects of static inter-qubit interactions and random errors in quantum gates on the stability of various quantum algorithms including the Grover quantum search algorithm and the quantum...
Phase diagram for the Grover algorithm with static imperfections (2004)
Pomeransky, A. A., Zhirov, O. V., Shepelyansky, D. L.
We study effects of static inter-qubit interactions on the stability of the Grover quantum search algorithm. Our numerical and analytical results show existence of regular and chaotic phases...
Zhirov, O. V., Casati, G., Shepelyansky, D. L.
We study analytically and numerically the one-dimensional quantum Frenkel-Kontorova chain in the regime when the classical model is located in the pinned phase characterized by the gaped phonon...
Fractal Spin Glass Properties of Low Energy Configurations in the Frenkel-Kontorova chain (2001)
Zhirov, O. V., Casati, G., Shepelyansky, D. L.
We study numerically and analytically the classical one-dimensional Frenkel-Kontorova chain in the regime of pinned phase characterized by phonon gap. Our results show the existence of exponentially...
Big Entropy Fluctuations in Statistical Equilibrium: The Macroscopic Kinetics (2000)
Chirikov, B. V., Zhirov, O. V.
Large entropy fluctuations in an equilibrium steady state of classical mechanics were studied in extensive numerical experiments on a simple 2--freedom strongly chaotic Hamiltonian model described by...
Quantum Resonances and Regularity Islands in Quantum Maps (1999)
Sokolov, V. V., Zhirov, O. V., Alonso, D., Casati, G.
We study analytically as well as numerically the dynamics of a quantum map near a quantum resonance of an order q. The map is embedded into a continuous unitary transformation generated by a...
Quantum Resonances of Kicked Rotor and SU(q) group (1999)
Sokolov, V. V., Zhirov, O. V., Alonso, D., Casati, G.
The quantum kicked rotor (QKR) map is embedded into a continuous unitary transformation generated by a time-independent quasi-Hamiltonian. In some vicinity of a quantum resonance of order $q$, we...
Density-Density Correlators in Infinite Random Matrices (1997)
Using the BRM theory developed recently by Fyodorov and Mirlin we calculate the density-density correlators for Banded Random Matrix of infinite size. Within the accuracy of $1/b^2$ ($b$ is the...
How long does the quantum chaos last? (1997)
Casati, Gulio, Chirikov, B. V., Zhirov, O. V.
The main purpose of this Comment is to point out that besides the short time scale of quantum chaos, confirmed once more in recent paper by Alicki et al, there is generally another time scale t_R,...