20th SmoleQ Greeting Seminar (2026.6.26 at 17:00 (JST))

 

Speaker: 

Tomohito Otobe

Title: 

SALMON (Scalable Ab-initio Light-Matter simulator for Optics and Nanoscience)

Abstract:

Real-time  time-dependent density functional theory (TDDFT) has become a powerful  approach for investigating ultrafast electron dynamics induced by  intense  laser fields. In this seminar, I will introduce the open-source  simulation package SALMON (Scalable Ab-initio Light-Matter simulator for  Optics and Nanoscience), which enables large-scale first-principles  simulations of light–matter interactions ranging from  linear optical responses to highly nonlinear and nonequilibrium  phenomena.

I  will present recent developments in SALMON and highlight several  applications, with a particular focus on valleytronics in  low-dimensional materials. These  studies reveal how ultrafast laser fields can selectively control  valley-dependent electronic excitations and transport phenomena,  providing microscopic insights into light-driven quantum  functionalities.

In  addition, I will discuss our recent efforts toward large-scale  electronic structure calculations based on divide-and-conquer (DC)  approaches. By combining  linear-scaling ground-state methods with real-time electron dynamics  simulations, we aim to extend first-principles studies to systems  containing thousands to tens of thousands of atoms, including realistic  heterogeneous materials and complex interfaces.

The  seminar will provide an overview of the current capabilities of SALMON  and future directions toward next-generation simulations of  nonequilibrium electron  dynamics in complex materials.