Quantum Dynamics in Noisy Backgrounds: from Sampling to Dissipation and Fluctuations

Autor(es)

Oliveira, O. ^{[1, 2]} ; de Paula, W. ^[2] ; Frederico, T. ^[2] ; Hussein, M. S. ^{[2, 3, 4]}

Afiliação do(s) autor(es)

^[1] Univ Coimbra, Dept Phys, CFisUC, P-3004516 Coimbra - Portugal

^[2] DCTA, Inst Tecnol Aeronaut, BR-12228900 Sao Jose Dos Campos - Brazil

^[3] Univ Sao Paulo, Inst Fis, Caixa Postal 66318, BR-05314970 Sao Paulo, SP - Brazil

^[4] Univ Sao Paulo, Inst Estudos Avancados, Caixa Postal 66318, BR-05314970 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Brazilian Journal of Physics; v. 46, n. 4, p. 384-392, AUG 2016.
• Citações Web of Science: 1

Resumo

We investigate the dynamics of a quantum system coupled linearly to Gaussian white noise using functional methods. By performing the integration over the noisy field in the evolution operator, we get an equivalent non-Hermitian Hamiltonian, which evolves the quantum state with a dissipative dynamics. We also show that if the integration over the noisy field is done for the time evolution of the density matrix, a gain contribution from the fluctuations can be accessed in addition to the loss one from the non-hermitian Hamiltonian dynamics. We illustrate our study by computing analytically the effective non-Hermitian Hamiltonian, which we found to be the complex frequency harmonic oscillator, with a known evolution operator. It leads to space and time localisation, a common feature of noisy quantum systems in general applications. (AU)

• Processo FAPESP: 14/08388-0 - Dinâmica não-perturbativa em teoria quântica de campos relativistas aplicadas ao grafeno e à cromodinâmica quântica
• Beneficiário: Tobias Frederico
• Modalidade de apoio: Auxílio à Pesquisa - Pesquisador Visitante - Internacional