News

Strain engineering of the magnetic multipole moments and anomalous Hall effect in pyrochlore iridate... Jul 22, 2020 l Hit 1265

The recent observation of the anomalous Hall effect (AHE) without notable magnetization in antiferromagnets has suggested that ferromagnetic ordering is not a necessary condition. Thus, recent theoretical studies have proposed that higher-rank magnetic multipoles formed by clusters of spins (cluster multipoles) can gen...

Coherent many-body exciton in van der Waals antiferromagnet NiPS3 Jul 22, 2020 l Hit 723

Excitons are the composite particles of an electron-hole pair and rarely observed for many-body states with strong correlation. Here we show that a rare spin-orbital entangled exciton state appears below TN=150 K in NiPS3, an antiferromagnetic (AFM) van der Waals (vdW) material. It arises intrinsically from the archety...

Momentum-dependent magnon lifetime in the metallic non-collinear triangular antiferromagnet CrB2 Jul 9, 2020 l Hit 1919

Noncollinear magnetic order arises for various reasons in several magnetic systems and exhibits interesting spin dynamics. Despite its ubiquitous presence, little is known of how magnons, otherwise stable quasiparticles, decay in these systems, particularly in metallic magnets. Using inelastic neutron scattering, we ex...

[Kok Chuan Tan, Seongjeon Choi, and Hyunseok Jeong] Negativity of Quasiprobability Distributions as ... Mar 26, 2020 l Hit 1334

We demonstrate that the negative volume of any s-parametrized quasiprobability, including the Glauber-Sudashan P-function, can be consistently defined and forms a continuous hierarchy of nonclassicality measures that are linear optical monotones. These measures belong to an operational resource theory of nonclassicalit...

[Sungjoon Park,Prof. Bohm-Jung Yang] Thermal Hall Effect, Spin Nernst Effect, and Spin Density Induc... Mar 13, 2020 l Hit 1483

We theoretically study the intrinsic thermal Hall and spin Nernst effect in collinear ferrimagnets on a honeycomb lattice with broken inversion symmetry. The broken inversion symmetry allows in-plane Dzyaloshinskii−Moriya interaction between the nearest neighbors, which does not affect the linear spin wave theory...

[KPS Award Winner] Junyeong Ahn (Ph.D. Candidate) received the Young Physicist Prize! Oct 29, 2019 l Hit 1935

Junyeong Ahn, a Ph.D Candidate at Prof. Bohm-Jung Yang's group, won the Young Physicist Prize at the KPS autumm meeting held at Gwangju, Kim Dae Joong convention center for Oct.23-25, 2019. The Prize is awarded for Junyeong's outstanding achievement about the band topology of wave functions in space-time inversi...

[Quantum Gas Lab] Kibble-Zurek universality in a strongly interacting Fermi superfluid (Nature Physi... Sep 18, 2019 l Hit 1716

Kibble-Zurek universality in a strongly interacting Fermi superfluid The Kibble-Zurek mechanism describes the spontaneous formation of topological defects in a system crossing a continuous phase transition. Its central premise is the notion of universality, which states that the characteristic scaling exponent describi...

[Jinsu Pak, Dr. Seungjun Chung, and Prof. Takhee Lee]  Intrinsic Optoelectronic Characteristics of M... Aug 2, 2019 l Hit 3202

In the past decade, intensive studies on monolayer MoS2-based phototransistors have been carried out to achieve further enhanced optoelectronic characteristics. However, the intrinsic optoelectronic characteristics of monolayer MoS2 have still not been explored until now because of unintended interferences, such as mul...

[Dr. Myungjae Lee, Prof. Heonsu Jeon] The paper “Taming of random lasers” chosen for the cover page ... Jul 2, 2019 l Hit 1758

The research paper “Taming of random lasers” by Prof. Heonsu Jeon’s group, published online in the last April, now appears in the cover of the July 2019 issue of Nature Photonics, along with the following introductory remarks: Random lasers are notorious for their unpredictability and uncontrollabilit...

[Changhee Lee, Prof. Hongki Min] Emergent Anisotropic Non-Fermi Liquid at a Topological Phase Transi... May 15, 2019 l Hit 880

Understanding correlation effects in topological phases and their transitions is a cutting-edge area of research in recent condensed matter physics. We study topological quantum phase transitions (TQPTs) between double-Weyl semimetals (DWSMs) and insulators, and argue that a novel class of quantum criticality appears a...