News

[Sungjoon Park, Yoonseok Hwang, Hong Chul Choi/ Prof. Bohm-Jung Yang] Topological acoustic triple po... Nov 24, 2021 l Hit 544

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 755

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 1387

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 2293

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 1254

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 1253

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 2467

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...

[Prof. Cheol-Hwan Park] Outstanding Referees of the American Physical Society Mar 3, 2021 l Hit 831

Professor Cheol-Hwan Park is selected and honored with the Outstanding Referee designation of the American Physical Society (APS). APS has selected 151 Outstanding Referees for 2021 who have demo...

[Sunghoon Kim, Joon-Hyuk Ko, Prof. Wonho Jhe ] Universal Theory of Dynamic Force Microscopy for Exac... Feb 25, 2021 l Hit 813

Force reconstruction in dynamic force microscopy (DFM) is a nontrivial problem that requires deconvolution of integrals. However, conventional reconstruction methods, which recover forces from single-frequency motion of the cantilever at its resonance, exhibit non-negligible error and reconstruction instability in the ...

[Seung Hun Lee, Hong Chul Choi, Prof. Bohm-Jung Yang] Odd-parity spin-triplet superconductivity in c... Feb 18, 2021 l Hit 788

We propose a route to achieve odd-parity spin-triplet (OPST) superconductivity in metallic collinear antiferromagnets with inversion symmetry. Owing to the existence of hidden antiunitary symmetry, which we call the effective time-reversal symmetry (eTRS), the Fermi surfaces of ordinary antiferromagnetic metals are gen...