RQC Seminar

39th RQC Seminar

• Speaker

  Mr. Yi-Te Huang　
  (National Cheng Kung University, Taiwan)

• Date

  16:00-17:00 (JST), April 12, 2023 (Wednesday)

• Venue

  Onsite (Wako Main Research 4F 435-437Meeting Room)

• Title

  An efficient Julia framework for hierarchical equations of motion in open quantum systems

• Inquiries

  rqc_info[at]ml.riken.jp

Abstract
We introduce an open-source software package called "Heom.jl", a Julia framework to integrate the hierarchical equations of motion (HEOM) for the reduced dynamics of a system simultaneously coupled to multiple bosonic and fermionic environments. Heom.jl features a collection of methods to compute bosonic and fermionic spectra, stationary states, and the full dynamics in the extended space of all auxiliary density operators (ADOs). The required handling of the ADOs multi-indexes is achieved through a user-friendly interface. We exemplify the functionalities of the package by analyzing a single impurity interacting with two fermionic reservoirs (Anderson model), and an ultra-strongly coupled charge-cavity system interacting with one bosonic and two fermionic reservoirs. Heom.jl allows for an order of magnitude speedup in the construction of the HEOM Liouvillian superoperator, solving dynamics and stationary states for all ADOs with respect to the corresponding method in the Quantum Toolbox in Python (QuTiP), upon which this package is founded.