JuliaCon 2026

Hiroharu Sugawara

Hiroharu Sugawara is an associate professor in the Graduate School of Systems Design at Tokyo Metropolitan University, Tokyo, Japan. He received his Ph.D. in electronic engineering from the University of Tokyo in 1994.
His research focuses on eco-friendly semiconductor functional materials.
He has been a Julia user since Julia 0.5.
He has been teaching a programming exercise course using the Julia language for university freshmen in the Department of Mechanical Systems Engineering every year since the 2018 academic year.

He translated Tanmay Bakshi's "Tanmay Teaches Julia for Beginners" into Japanese (ISBN 978-4807920211) in 2022.


Sessions

08-13
16:00
15min
BoltzTraP.jl: Thermoelectric transport for the Julia DFT ecosystem
Hiroharu Sugawara

Seebeck coefficient, electrical conductivity, and thermal conductivity are key parameters for thermoelectric design. BoltzTraP.jl is a Julia port of BoltzTraP2, the standard tool for computing these via the Boltzmann transport equation, ensuring numerical equivalence with Julia-native optimizations. It accepts input from major DFT codes and DFTK.jl, enabling an all-Julia workflow from electronic structure to transport properties. In-memory calculations show over 2x speedup over BoltzTraP2.

JuliaMolSim Minisymposium
Room 2
08-14
15:45
15min
PhoXonic.jl: Unified interface for calculating photonic and phononic bandgaps with pure Julia
Hiroharu Sugawara

Periodic structures create band gaps that restrict electromagnetic and elastic wave propagation. These gaps enable control of light and sound at the wavelength scale. PhoXonic.jl is the first pure Julia tool computing both photonic and phononic dispersion relations through a unified interface using plane wave expansion. It supports 1D, 2D, and 3D with dense and sparse solvers, and includes topological invariant analysis. Results reproduce published literature.

General
Room 3
08-14
16:00
15min
Microstructure Simulation in Pure Julia: Phase Fields with CALPHAD Coupling
Hiroharu Sugawara

The phase field method simulates microstructure evolution and phase transitions. PhaseFields.jl is the first pure Julia package providing major phase field models with built-in FDM and FEM (via Gridap.jl) and adaptive time stepping (DifferentialEquations.jl). It couples with OpenCALPHAD.jl for chemical potentials via automatic differentiation from CALPHAD databases. We demonstrate spinodal decomposition, CALPHAD-driven solidification, and Stefan problem validation.

General
Room 3