Nanoscale heat transfer

Heat transfer in nanostructures exhibits extraordinary behaviors due to tailored phonon scatterings. Phononic nanostructures promise unprecedented heat control technologies such as tunable anisotropy, directional heat sink, and heat shield, as well as microthermoelectrics.

B. Kim et al., ACS Nano 18 (15), 10557–10565 (2024)

S. Tachikawa,  ... B. Kim et al., Physical Review Letters 132 (18), 186904 (2024)

Hypersonic phononic crystals, optomechanics

Hypersonic acoustic waves (~GHz) play a crucial role in quantum interfaces that connect the significant frequency gap of 4 to 5 orders of magnitude between microwave and optical photons. Designing a efficient phononic interface is a pivotal mission for coherent, high-speed modulators and filters with suppresed heat generation.  

B. Kim et al., Physical Review Applied 20 (4), 044037 (2023)

M. Diego, B. Kim et al., Physical Review Applied 21, 064064 (2024)

M. Diego, M. Pirro, B. Kim et al., ACS Nano 18 (28), 18307-18313 (2024)

Laser micromachining

Laser micromachining is a fast and enviroment-friendly method which can be applied for most of materials including metals, semiconductors, dielectrics, polymers, and biomaterials. By means of ultrashort lasers, we conduct precision fabrication of nano/microscturctures. Our machining topics cover

1. Thin film ablation (including LIPSS) and transfer

2. Laser-direct-writing of multifunctional electronic and optical devices based on laser-induced graphene (LIG) with consideration of the thermal management

3. Through substrate vias

4. Optothermal analysis taking into account two-temperature model and nonlinear optics. 

B. Kim et al., Advanced Optical Materials, 2500498 (2025)  
B. Kim et al., International Journal of Precision Engineering and Manufacturing-Green Technology 8, 771-782 (2020)

T.-S. D. Le et al., Advanced Functional Materials 32, 2107768 (2021)

B. Kim et al., Applied Surface Science 565, 150595 (2021)

Extreme ultraviolet generation and applications

Extreme ultraviolet (EUV) radiation, with wavelengths ranging from 10 to 120 nm, plays a crucial role in contemporary semiconductor manufacturing, inspection technologies, and electronic spectroscopy. Its significance has been underscored by the 2023 Nobel Prize in Physics awarded for advancements in attosecond pulse generation using EUV radiation. Our research focuses on developing innovative methods to manipulate and enhance EUV radiation using tabletop instruments. 

B. Kim, S. Choi et al., ACS Photonics 10 (10), 3458-3466 (2023)

Y. W. Kim, B. Kim, S. Choi et al., Optics and Laser Technology 145, 107507 (2022)

S. Won, S. Choi... B. Kim et al., Nanophotonics 12 (16), 3373-3383 (2023)