Publications (20)
Spontaneous structural distortion of metallic Shastry-Sutherland system DyB4 by quadrupole-spin-lattice coupling
Hasung Sim, Seongsu Lee, Kun-Pyo Hong +10
DyB4 has a two-dimensional Shastry-Sutherland (Sh-S) lattice with strong Ising character of the Dy ions. Despite the intrinsic frustrations, surprisingly, it undergoes two successi…
Thermal Hall effects due to topological spin fluctuations in YMnO
Ha-Leem Kim, Takuma Saito, Heejun Yang +7
The thermal Hall effect in magnetic insulators has been considered a powerful method for examining the topological nature of charge-neutral quasiparticles such as magnons. Yet, unl…
Low-energy spin dynamics of orthoferrites AFeO (A = Y, La, Bi)
Kisoo Park, Hasung Sim, Jonathan C. Leiner +9
YFeO and LaFeO are members of the rare-earth orthoferrites family with \textit{Pbnm} space group. Using inelastic neutron scattering, the low-energy spin excitations have b…
The -Electron Heisenberg Pyrochlore MnSbO
Darren C. Peets, Hasung Sim, Maxim Avdeev +1
In frustrated magnetic systems, geometric constraints or the competition amongst interactions introduce extremely high degeneracy and prevent the system from readily selecting a lo…
Robust singlet dimers with fragile ordering in two-dimensional honeycomb lattice of LiRuO
Junghwan Park, Teck-Yee Tan, D. T. Adroja +14
When an electronic system has strong correlations and a large spin-orbit interaction, it often exhibits a plethora of mutually competing quantum phases. How a particular quantum gr…
Symmetry breaking and unconventional charge ordering in single crystal NaRuO
Arvind Yogi, C. I. Sathish, Hasung Sim +3
The interplay of charge, spin, and lattice degrees of freedom in matter leads to various forms of ordered states through phase transitions. An important subclass of these phenomena…
Doping effects on trimerization and magnetoelectric coupling of single crystal multiferroic (Y,Lu)MnO3
Seongil Choi, Hasung Sim, Sunmin Kang +2
Hexagonal RMnO3 is a multiferroic compound with a giant spin-lattice coupling at an antiferromagnetic transition temperature [1]. Despite extensive studies over the past two decade…
High-resolution structure studies and magnetoelectric coupling of relaxor multiferroic Pb(FeNb)O
Hasung Sim, Darren C. Peets, Sanghyun Lee +6
Pb(FeNb)O (PFN), one of the few relaxor multiferroic systems, has a -type antiferromagnetic transition at = 143 K and a ferroelectric transition at $T_…
Properties of spin 1/2 triangular lattice antiferromagnets: CuRE2Ge2O8 (RE=Y, La)
Hwanbeom Cho, Marie Kratochvilova, Hasung Sim +10
We found new two-dimensional (2D) quantum (S=1/2) antiferromagnetic systems: CuRE2Ge2O8 (RE=Y and La). According to our analysis of high-resolution X-ray and neutron diffraction ex…
Renormalization of spin excitations in hexagonal HoMnO3 by magnon-phonon coupling
Taehun Kim, Jonathan C. Leiner, Kisoo Park +5
Hexagonal HoMnO3, a two-dimensional Heisenberg antiferromagnet, has been studied via inelastic neutron scattering. A simple Heisenberg model with a single-ion anisotropy describes…
Magnetoelectric domain engineering from micrometer to à ngstrøm scales
Marcela Giraldo, Arkadiy Simonov, Hasung Sim +8
The functionality of magnetoelectric multiferroics depends on the formation, size, and coupling of their magnetic and electric domains. Knowing the parameters guiding these criteri…
Coexisting Z-type charge and bond order in metallic NaRuO
Arvind Kumar Yogi, Alexander Yaresko, C. I. Sathish +7
How particular bonds form in quantum materials has been a long-standing puzzle. Two key concepts dealing with charge degrees of freedom are dimerization (forming metal-metal bonds)…
Analysis of one-dimensional Yut-Nori game: winning strategy and avalanche-size distribution
Hye Jin Park, Hasung Sim, Hang-Hyun Jo +1
In the Korean traditional board game Yut-Nori, teams compete by moving their pieces on the two-dimensional game board, and the team whose all pieces complete a round trip on the bo…
Hexagonal RMnO: a model system for 2D triangular lattice antiferromagnets
Hasung Sim, Joosung Oh, Jaehong Jeong +2
The hexagonal RMnO (h-RMnO) are multiferroic materials, which exhibit the coexistence of a magnetic order and ferroelectricity. Their distinction is in their geometry that…
Frustrated antiferromagnetic honeycomb-tunnel-like lattice CuRE2Ge2O8 (RE=Pr, Nd, Sm, and Eu)
Hwanbeom Cho, Marie Kratochvilova, Nahyun Lee +2
New frustrated antiferromagnetic compounds CuRE2Ge2O8 (RE=Pr, Nd, Sm, Eu) have been investigated using high-resolution x-ray diffraction, magnetic and heat capacity measurements. T…
Spin texture induced by non-magnetic doping and spin dynamics in 2D triangular lattice antiferromagnet h-Y(Mn,Al)O3
Pyeongjae Park, Kisoo Park, Joosung Oh +14
Novel effects induced by nonmagnetic impurities in frustrated magnets and quantum spin liquid represent a highly nontrivial and interesting problem. A theoretical proposal of exten…
Spin glass behavior in frustrated quantum spin system CuAl2O4 with a possible orbital liquid state
R. Nirmala, Kwang-Hyun Jang, Hasung Sim +10
CuAl2O4 is a normal spinel oxide having quantum spin, S=1/2 for Cu2+. It is a rather unique feature that the Cu2+ ions of CuAl2O4 sit at a tetrahedral position, not like the usual…
Spontaneous decays of magneto-elastic excitations in noncollinear antiferromagnet (Y,Lu)MnO3
Joosung Oh, Manh Duc Le, Ho-Hyun Nahm +12
When magnons and phonons, the fundamental quasiparticles of the solid, are coupled to one another, they form a new hybrid quasi-particle, leading to novel phenomena and interesting…
Studies on the high-temperature ferroelectric transition of multiferroic hexagonal manganite RMnO3
Hasung Sim, Jaehong Jeong, Haeri Kim +2
Hexagonal manganites are multiferroic materials with two highly-dissimilar phase transitions: a ferroelectric transition (from P63/mmc to P63cm) at a temperature higher than 1000 K…
Magnetic Transitions in the Chiral Armchair-Kagome System MnSbO
Darren C. Peets, Hasung Sim, Seongil Choi +6
The competition between interactions in frustrated magnets allows a wide variety of new ground states, often exhibiting emergent physics and unique excitations. Expanding the suite…