We use Fourier transform infrared (FTIR) spectrometers and a monochromatic type optical spectrometer to cover a broad spectral range from far infrared (FIR) through ultraviolet (UV). We investigate low-lying (or intraband) optical excitations, characteristic collective modes including pure and hybrid phonon modes, and electronic (interband) transitions of various novel quantum material systems. The quantum material systems would be
Unconventional superconductors: High-temperature superconductors (copper oxides and Fe-pnictides) and heavy fermion systems
Strongly Correlated electron systems: bulk d- or f- electron systems and 3d transition metal oxide superlattice systems
Low-dimensional system: graphene, graphite, transition metal dichalcogenides (TMD), copper thin films etc.
Photovoltaic materials: organic solar cells.
We also would like to contribute other research areas of science such as astrophysics by sharing my spectroscopy technique and knowledge through close collaborations.
Journal Articles
(2024)
An inversion problem for optical spectrum data via physics‑guided machine learning.
SCIENTIFIC REPORTS.
14,
2024
(2024)
Solving inverse problems using normalizing flow prior: Application to optical spectra.
PHYSICAL REVIEW B.
109,
16
(2024)
Effect of Cd- and Sn-doping in CeCoIn5 on the hybridization gap and f -electron amplitude studied with infrared spectroscopy.
PHYSICAL REVIEW B.
109,
12
(2024)
Planckian behavior of cuprates at the pseudogap critical point simulated via flat electron-boson spectral density.
HELIYON.
10,
2024
(2023)
Role of electron–phonon coupling in the superconducting state of MgB2 polycrystals fabricated at different conditions.
CERAMICS INTERNATIONAL.
49,
2023
(2023)
Roles of Fe-ion irradiation on MgB2 thin films: Structural, superconducting, and optical properties.
JOURNAL OF ALLOYS AND COMPOUNDS.
968,
2023
(2023)
Self-Oxidation Resistance of the Curved Surface of Achromatic Copper.
ADVANCED MATERIALS.
2023,
2023
(2023)
Geometrical Doping at the Atomic Scale in Oxide Quantum Materials.
ACS NANO.
17,
15
(2023)
Bosonic spectrum of a correlated multiband system, BaFe1.80Co0.20As2, obtained via infrared spectroscopy.
RESULTS IN PHYSICS.
50,
2023
(2023)
Robust Excitonic-Insulating States in Cu-Substituted Ta<sub>2</sub>NiSe<sub>5</sub>.
ADVANCED MATERIALS INTERFACES.
10,
12
(2023)
Temperature-dependent f-electron evolution in CeCoIn5 via a comparative infrared study with LaCoIn5.
RESULTS IN PHYSICS.
47,
2023
(2023)
Fermi liquid-like behaviour of cuprates in the pseudogap phase simulated via <i>T</i>-dependent electron-boson spectral density.
SCIENTIFIC REPORTS.
13,
1
(2023)
Coherent consolidation of trillions of nucleations for mono-atom step-level flat surfaces.
NATURE COMMUNICATIONS.
14,
1
(2022)
Doping-dependent superconducting physical quantities of K-doped BaFe2 As-2 obtained through infrared spectroscopy.
SCIENTIFIC REPORTS.
12,
1
(2022)
Formation of optically-active disordered layers in (001) MgO single crystals.
CURRENT APPLIED PHYSICS.
46,
2023
(2022)
Correlation effects obtained from optical spectra of Fe-pnictides using an extended Drude-Lorentz model analysis.
CURRENT APPLIED PHYSICS.
39,
1
(2022)
Unusually large exciton binding energy in multilayered 2H-MoTe2.
SCIENTIFIC REPORTS.
12,
1
(2021)
Electron-boson spectral density functions of cuprates obtained from optical spectra via machine learning.
PHYSICAL REVIEW B.
104,
23
(2021)
Stellar interferometry for gravitational waves.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS.
2021,
11
(2021)
Evolution of the electronic structure of Ru-doped single-crystal iridates Sr2Ir1-xRuxO4.
PHYSICAL REVIEW B.
104,
16
