Sensitivity to parameters of STIRAP in a Cooper Pair Box

Sensitivity to parameters of STIRAP in a Cooper Pair Box

The rapid experimental progress in the field of superconducting nanocircuits gives rise to an increasing quest for advanced quantum-control techniques for these macroscopically coherent systems. Here we demonstrate theoretically that stimulated Raman adiabatic passage (STIRAP), a well-established method in quantum optics, should be possible with the quantronium setup of a Cooperpair box. We fin...

Coherent oscillations in a Cooper-pair box

– This paper is devoted to an analysis of the experiment by Nakamura et al. (Nature 398, 786 (1999)) on the quantum state control in Josephson junctions devices. By considering the relevant processes involved in the detection of the charge state of the box and a realistic description of the gate pulse we are able to analyze some aspects of the experiment (like the amplitude of the measurement c...

Rapid-state purification protocols for a Cooper pair box

Entanglement and decoherence of a micromechanical resonator via coupling to a Cooper-pair box.

We analyze the quantum dynamics of a micromechanical resonator capacitively coupled to a Cooper-pair box. With appropriate quantum state control of the Cooper box, the resonator can be driven into a superposition of spatially separated states. The Cooper box can also be used to probe the decay of the resonator superposition state due to environmental decoherence.

Coherent-incoherent transition in a Cooper-pair-box coupled to a quantum oscillator: an equilibrium approach

Abstract: Temperature effect on quantum tunneling in a Cooper-pair-box coupled to a quantum oscillator is studied by both numerical and analytical calculations. It is found that, in strong coupling regions, coherent tunneling of a Cooper-pair-box can be destroyed by its coupling to a quantum oscillator and the tunneling becomes thermally activated as the temperature rises, leading to failure of...