A driven damped harmonic oscillator in the ket-vector representation of the density operator

“…A resonant drive of the electron level with amplitude A can be mapped to a vibron drive given by iA (a † e − iΩ dr t −a e iΩ dr t ), where A = AΩ/(2λ). If we in addition introduce a vibron damping rate γ to prevent divergences that might arise from driving a part of the bath, this generates the coherent vibron state 36 |δ with δ ∝ iA /(Ω dr − Ω + iγ). Therefore, we consider the vibron density matrix ρ (δ) vib = |δ δ|.…”

Section: Vibron In a Coherent Statementioning

confidence: 99%

Lifting the Franck-Condon blockade in driven quantum dots

et al. 2016

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Electron-vibron coupling in quantum dots can lead to a strong suppression of the average current in the sequential tunneling regime. This effect is known as Franck-Condon blockade and can be traced back to an overlap integral between vibron states with different electron numbers which becomes exponentially small for large electron-vibron coupling strength. Here, we investigate the effect of a time-dependent drive on this phenomenon, in particular the effect of an oscillatory gate voltage acting on the electronic dot level. We employ two different approaches: perturbation theory based on nonequilibrium Keldysh Green's functions and a master equation in Born-Markov approximation. In both cases, we find that the drive can lift the blockade by exciting vibrons. As a consequence, the relative change in average current grows exponentially with the drive strength.

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“…( 5) is eigen-vector of. (6) Obviously, When (7) And it is obtain that (8) By means of technique (IWOP), one can prove that makes up a complete and orthonormal set (9) And, it is convenient to introduce the state [15] for density operator (10) This means that we can uniquely represent any density operator of physical mode by vector from the two-mode Hilbert space. This vector contains all information on the quantum state as the density operator.…”

Section: Brief Review Of the Thermo Entangled State Representationmentioning

confidence: 99%

“…It is difficult to solve Eq. ( 22) therefore we define "dissipative interaction picture" in entangled representation [14,15] for ρ ± (t) as follows:…”

Section: Unraveling Master Equations Through Entangled State Represen...mentioning

confidence: 99%

New approach to solving master equations of density operator for the Jaynes Cummings model with cavity damping

Ashrafi¹,

Bazrafkan²

2014

Chinese Phys. B

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By introducing thermo-entangled state representation , which can map master equations of density operator in quantum statistics as state-vector evolution equations, and using ''dissipative interaction picture we solve the master equation of Jaynes-Cummings model with cavity damping. In addition we derive the Wigner function for density operator when the atom is initially in the up state and the cavity mode is in coherent state.

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A driven damped harmonic oscillator in the ket-vector representation of the density operator

Cited by 4 publications

References 9 publications

Unraveling a Driven Damped Harmonic Oscillator through Entangled State Representation

Unraveling a Driven Damped Harmonic Oscillator through Entangled State Representation

Lifting the Franck-Condon blockade in driven quantum dots

New approach to solving master equations of density operator for the Jaynes Cummings model with cavity damping

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