Efficient finite-time measurements under thermal regimes

Autor(es)

Brasil, Carlos Alexandre ^[1] ; de Castro, Leonardo Andreta ^[2] ; Napolitano, Reginaldo de Jesus ^[2]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP - Brazil

^[2] Univ Sao Paulo, Inst Fis Sao Carlos, BR-13560970 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: EUROPEAN PHYSICAL JOURNAL PLUS; v. 129, n. 10 OCT 1 2014.
• Citações Web of Science: 2

Resumo

Contrary to conventional quantum mechanics, which treats measurement as instantaneous, here we explore a model for finite-time measurement. The main two-level system interacts with the measurement apparatus in a Markovian way described by the Lindblad equation, and with an environment, which does not include the measuring apparatus. To analyse the environmental effects on the final density operator, we use the Redfield approach, allowing us to consider a non-Markovian noise. In the present hybrid theory, to trace out the environmental degrees of freedom, we use a previously developed analytic method based on superoperator algebra and Nakajima-Zwanzig superoperators. Here, we analyse two types of system-environment interaction, phase and amplitude damping, which allows us to conclude that, in general, a finite-time quantum measurement performed during a certain period is more efficient than an instantaneous measurement performed at the end of it, because the rate of change of the populations is attenuated by the system-measurement apparatus interaction. (AU)

• Processo FAPESP: 11/19848-4 - Influência do tempo de medida em fenômenos relacionados à informação quântica
• Beneficiário: Carlos Alexandre Brasil
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado