News

[Jae-Mo Lihm and Prof. Cheol-Hwan Park] Development of Wannier Function Perturbation Theory Dec 23, 2021 l Hit 883

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 1821

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 823

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...

[Sungjoon Park, Yoonseok Hwang, Hong Chul Choi/ Prof. Bohm-Jung Yang] Topological acoustic triple po... Nov 24, 2021 l Hit 610

Acoustic phonon is a classic example of triple degeneracy point in band structure. This triple point always appears in phonon spectrum because of the Nambu–Goldstone theorem. Here, we show that this triple point can carry a topological charge q that is a property of three-band systems with space-time-inversion sy...

[Yoonseok Hwang, Prof. Bohm-Jung Yang] Geometric characterization of anomalous Landau levels of isol... Nov 8, 2021 l Hit 860

According to the Onsager’s semiclassical quantization rule, the Landau levels of a band are bounded by its upper and lower band edges at zero magnetic field. However, there are two notable systems where the Landau level spectra violate this expectation, including topological bands and flat bands with singular ban...

[Dr. Taehun Kim, Prof. Je-Geun Park] Slow oxidation of magnetite nanoparticles elucidates the limits... Nov 8, 2021 l Hit 1455

Magnetite (Fe3O4) is of fundamental importance for Verwey transition near TV = 125 K, below which a complex lattice distortion and electron orders occur. Verwey transition is suppressed by chemical doping effects giving rise to well-documented first and second-order regimes, but the origin of the order change is unclea...

[Wonjin Jang, Min-Kyun Cho / Prof. Dohun Kim] Single-Shot Readout of a Driven Hybrid Qubit in a GaAs... Jun 15, 2021 l Hit 2353

We report a single-shot-based projective readout of a semiconductor hybrid qubit formed by three electrons in a GaAs double quantum dot. Voltage-controlled adiabatic transitions between the qubit operations and readout conditions allow high-fidelity mapping of quantum states. We show that a large ratio both in relaxati...

[Youjin Lee, Prof. Kee Hoon Kim and Prof. Je-Geun Park] Possible persistence of multiferroic order d... Jun 8, 2021 l Hit 1348

Realizing a state of matter in two dimensions has repeatedly proven a novel route of discovering new physical phenomena. Van der Waals (vdW) materials have been at the center of these now extensive research activities. They offer a natural way of producing a monolayer of matter simply by mechanical exfoliation. This wo...

[Pyeongjae Park, Kisoo Park and Prof. Je-Geun Park] Spin texture induced by non-magnetic doping and ... Apr 20, 2021 l Hit 1351

Novel effects induced by nonmagnetic impurities in frustrated magnets and quantum spin liquid represent a highly nontrivial and interesting problem. A theoretical proposal of extended modulated spin structures induced by doping of such magnets, distinct from the well-known skyrmions has attracted significant interest. ...

[Daeho Yang, Seunghoon Oh, Junseok Han, Gibeom Son, Jinuk Kim and Kyungwon An] Realization of supera... Mar 8, 2021 l Hit 2672

Superabsorption refers to a 'super' version of absorption just like superradiance is a 'super' version of emission. In superabsorption, correlated atoms collectively absorb light. The light can be absorbed completely and the number of absorbed photons is proportional to the square of the number of atoms. Although super...