RQC Seminar

152nd RQC Seminar

• Speaker

  Mr. Gerardo Suarez
  ( Gdansk University, ICTQT, Poland )

• Date

  16:00-17:00, August 27, 2024 (Tuesday)

• Venue

  Onsite( Wako Main Research 3F 345-347 Seminar Room/ 研究本館3階 セミナー室(345-347) C01）

• Title

  A CPTP candidate for Non-Markovian dynamics

• Inquiries

  rqc_info[at]ml.riken.jp

Abstract
The cumulant equation or refined weak coupling offers means to capture non-Markovian effects while adhering to the condition of being a Completely Positive Trace-Preserving (CPTP) evolution. This unique attribute distinguishes it from other approaches such as the Redfield equation which have negativity issues. On the other hand, the cumulant equation may allow for analytical calculations by means of its so-called regularizations. We will provide an overview of the equation as well as a comparison to other open systems descriptions, we'll take a look whether the steady state of this equation and compare it with an "exact" approach, namely the Mean Force Hamiltonian to show its benefits with respect to other approaches. Finally, we will show how one can use insights of exact methodologies to extend this formalism.

References:
Suárez, G., Łobejko, M., ＆ Horodecki, M. (2024, March 7). Dynamics of the non-equilibrium spin boson model: A benchmark of master equations and their validity. arXiv.org. https://arxiv.org/abs/2403.04488
Winczewski, M., Mandarino, A., Suarez, G., Alicki, R., ＆ Horodecki, M. (2024, August 5). Intermediate-Times Dilemma for open quantum system: Filtered approximation to the refined weak-coupling limit. Physical Review E. https://journals.aps.org/pre/abstract/10.1103/PhysRevE.110.024110
Łobejko, M., Winczewski, M., Suárez, G., Alicki, R., ＆ Horodecki, M. (2024, July 29). Corrections to the hamiltonian induced by finite-strength coupling to the environment. Physical Review E. https://journals.aps.org/pre/abstract/10.1103/PhysRevE.110.014144