Spin decoherence from Hamiltonian dynamics in quantum dots

Rao, D. D. Bhaktavatsala; Ravishankar, V.; Subrahmanyam, V.

doi:10.1103/physreva.74.022301

Cited by 22 publications

(28 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Hence, we need to know the steady-state entanglement in the two TLSs. We note that entanglement dynamics in similar systems has been studied [44]. In the following we apply the concurrence to quantify the steady-state entanglement in the two TLSs.…”

Section: Steady-state Entanglement Between the Two Tlssmentioning

confidence: 99%

Quantum thermalization of two coupled two-level systems in eigenstate and bare-state representations

2011

View full text Add to dashboard Cite

We study analytically the quantum thermalization of two coupled two-level systems (TLSs), which are connected with either two independent heat baths (IHBs) or a common heat bath (CHB). We understand the quantum thermalization in eigenstate and bare-state representations when the coupling between the two TLSs is stronger and weaker than the TLS-bath couplings, respectively. In the IHB case, we find that when the two IHBs have the same temperatures, the two coupled TLSs in eigenstate representation can be thermalized with the same temperature as those of the IHBs. However, in the case of two IHBs at different temperatures, just when the energy detuning between the two TLSs satisfies a special condition, the two coupled TLSs in eigenstate representation can be thermalized with an immediate temperature between those of the two IHBs. In bare-state representation, we find a counterintuitive phenomenon that, under some conditions, the temperature of the TLS connected with the high-temperature bath is lower than that of the other TLS, which is connected with the low-temperature bath. In the CHB case, the coupled TLSs in eigenstate representation can be thermalized with the same temperature as that of the CHB in nonresonant cases. In bare-state representation, the TLS with a larger energy separation can be thermalized to a thermal equilibrium with a lower temperature. In the resonant case, we find a phenomenon of anti-thermalization. We also study the steady-state entanglement between the two TLSs in both the IHB and CHB cases.

show abstract

Section: Steady-state Entanglement Between the Two Tlssmentioning

confidence: 99%

Quantum thermalization of two coupled two-level systems in eigenstate and bare-state representations

2011

View full text Add to dashboard Cite

show abstract

“…Recent work suggests that the internal dynamics of the environment can be crucial to the decoherence of the central system. [3][4][5][6][7][8][9][10][11][12][13][14][15] In this paper, we present results of extensive simulation work of a two-spin system interacting with a spin-bath environment and show that the decoherence of the two-spin system can exhibit different behaviors, depending on the characteristics of the coupling with the environment, the internal dynamics, and the initial state of the latter. We also provide a simple physical picture to understand this behavior.…”

Section: Introductionmentioning

confidence: 99%

Decoherence by a spin thermal bath: Role of spin-spin interactions and initial state of the bath

2008

View full text Add to dashboard Cite

We study the decoherence of two coupled spins that interact with a spin-bath environment. It is shown that the connectivity and the coupling strength between the spins in the environment are of crucial importance for the decoherence of the central system. For the anisotropic spin-bath, changing the connectivity or coupling strenghts changes the decoherence of the central system from Gaussian to exponential decay law. The initial state of the environment is shown to affect the decoherence process in a qualitatively significant manner.

show abstract

“…Spin baths have been studied [9]- [16] as an alternative to the conventional oscillator models of quantum dissipation [1,2]. They are known to give rise to non-Markovian evolution, with the system evolution showing a strong dependence on the polarization of the initial state [17].…”

Section: Introductionmentioning

confidence: 99%