Loading...

Thermal effects on coherence and excitation transfer

Memarzadeh, L ; Sharif University of Technology

647 Viewed
  1. Type of Document: Article
  2. DOI: 10.1103/PhysRevA.96.042318
  3. Abstract:
  4. To control and utilize quantum features in small scale for practical applications such as quantum transport, it is crucial to gain a deep understanding of the quantum characteristics of states such as coherence. Here by introducing a technique that simplifies solving the dynamical equation, we study the dynamics of coherence in a system of qubits interacting with each other through a common bath at nonzero temperature. Our results demonstrate that depending on the initial state, the environment temperature affects coherence and excitation transfer in different ways. We show that when the initial state is incoherent, as time goes on, coherence and the probability of excitation transfer increase. But for a coherent initial state, we find a critical value of temperature below which the system loses its coherence in time, which diminishes the probability of excitation transfer. Hence, in order to achieve a higher value of coherence and also a higher probability of excitation transfer, the temperature of the bath should go beyond that critical value. Stationary coherence and the probability of finding excited qubits in a steady state are discussed. We also elaborate on the dependence of the critical value of the bath temperature on system size. © 2017 American Physical Society
  5. Keywords:
  6. Excited states ; Probability ; Quantum chemistry ; Quantum computers ; Quantum electronics ; Quantum optics ; Bath temperatures ; Critical value ; Dynamical equation ; Environment temperature ; Excitation transfer ; Nonzero temperature ; Quantum features ; Quantum transport ; Quantum theory
  7. Source: Physical Review A ; Volume 96, Issue 4 , 2017 ; 24699926 (ISSN)
  8. URL: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.96.042318