News

[Ju-Yeon Gyhm] Quantum Charging Advantage Cannot Be Extensive Without Global Operations Apr 13, 2022 l Hit 1155

Quantum batteries are devices made from quantum states, which store and release energy in a fast and efficient manner, thus offering numerous possibilities in future technological applications. They offer a significant charging speedup when compared to classical batteries, due to the possibility of using entangling cha...

[Quantum Gas Lab.] Universal Early Coarsening of Quenched Bose Gases Apr 7, 2022 l Hit 906

We investigate the early coarsening dynamics of an atomic Bose gas quenched into a superfluid phase. Using a two-step quench protocol, we independently control the two cooling rates during and after passing through the critical region, respectively, and measure the number of quantum vortices spontaneously created in th...

[Jaeyoung Kim, Kyungjune, Prof. Keehoon Kang, and Prof. Takhee Lee] Channel-Length-Modulated Avalanc... Apr 6, 2022 l Hit 664

Recently there has been growing interest in avalanche multiplication in two-dimensional (2D) materials and device applications such as avalanche photodetectors and transistors. Previous studies have mainly utilized unipolar semiconductors as the active material and focused on developing high-performance ...

[Eunho Song and Prof. Sungchul Hohng] Rho-dependent transcription termination proceeds via three rou... Apr 1, 2022 l Hit 747

Rho-dependent transcription termination proceeds via three routes Rho is a general transcription termination factor in bacteria, but many aspects of its mechanism of action are unclear. Diverse models have been proposed for the initial interaction between the RNA polymerase (RNAP) and Rho (catch-up and stand-by pre-ter...

[Dowon Song and Prof. Kookrin Char] High-k perovskite gate oxide for modulation beyond 1014 cm-2 Mar 24, 2022 l Hit 579

Scaling down of semiconductor devices requires high-k dielectric materials to continue lowering the operating voltage of field-effect transistors (FETs) and storing sufficient charge on a smaller area. Here, we investigate the dielectric properties of epitaxial BaHf0.6Ti0.4O3 (BHTO), an alloy of perovskite ox...

[Dr. Suhan Son, Youjin Lee and Prof. Je-Geun Park] Multiferroic Enabled Magnetic‐exciton in 2D Quant... Jan 13, 2022 l Hit 651

Matter‐light interaction is at the center of diverse research fields from quantum optics to condensed matter physics, opening new fields like laser physics. A magnetic exciton is one such rare example found in magnetic insulators. However, it is relatively rare to observe that external variables control matter‐light in...

[Dongjin Oh and Prof. Changyoung Kim] B1g-Phonon Anomaly Driven by Fermi Surface Instability at Inte... Dec 30, 2021 l Hit 632

We performed temperature- and doping-dependent high-resolution Raman spectroscopy experiments on YBa2Cu3O7-δ to study B1g phonons. The temperature dependence of the real part of the phonon self-energy shows a distinct kink at T = TB1g above Tc due to softening, in addition to the one due to the onset of the super...

[Jae-Mo Lihm and Prof. Cheol-Hwan Park] Development of Wannier Function Perturbation Theory Dec 23, 2021 l Hit 777

Abstract: Thanks to the nearsightedness principle, the low-energy electronic structure of solids can be represented by localized states such as the Wannier functions. Wannier functions are actively being applied to a wide range of phenomena in condensed matter systems. However, the Wannier-function-based representation...

[Hyunsoo Ha, Prof. Bohm-Jung Yang] Colossal angular magnetoresistance in ferrimagnetic nodal-line se... Nov 25, 2021 l Hit 1724

Efficient magnetic control of electronic conduction is at the heart of spintronic functionality for memory and logic applications1,2. Magnets with topological band crossings serve as a good material platform for such control, because their topological band degeneracy can be readily tuned by spin configurations, dramati...

[Dr. Tae Yun Kim and Prof. Cheol-Hwan Park] Magnetic anisotropy and magnetic ordering of transition-... Nov 25, 2021 l Hit 734

A magnetic model with an unprecedentedly large number of parameters was determined from first-principles calculations for transition-metal phosphorus trisulfides (TMPS3’s), reproducing the measured magnetic ground states of bulk TMPS3’s. Our Monte Carlo simulations for the critical temperature, magnetic sus...