Autobiography of Yoshitaka Tanimura

TL;DR

This paper reviews the development of the hierarchical equations of motion for open quantum systems and ultrafast nonlinear 2D spectroscopy, highlighting their applications in quantum dynamics and photosynthesis research.

Contribution

It provides a historical and theoretical overview of HEOM and 2D spectroscopy, emphasizing their origins and applications in various quantum systems.

Findings

Development of HEOM for open quantum systems

Advancement of 2D spectroscopy for quantum coherence analysis

Applications in photosynthetic and solid-state systems

Abstract

In this paper, two developments, the theory of hierarchical equations of motion (HEOM) for open quantum dynamics systems and the theory of ultrafast nonlinear two-dimensional (2D) spectroscopies, are described, following the history of their founder. The HEOM was discovered by attempting to derive an equation similar to Kuob's stochastic Liouville equation based on the system-bath Hamiltonian. The theory of 2D spectroscopy was developed in the process of investigating the effect of quantum coherence on nonlinear vibrational spectra based on the Feynman-Vernon influence functional. The paper also describes the development of these two theories for problems such as electron and exciton transfer in photosynthetic systems, quantum statistical thermodynamics, and solid-state physics.