Publications by authors named "Soonmin Kang"

With the advanced investigations into low-dimensional systems, it has become essential to find materials having interesting lattices that can be exfoliated down to monolayer. One particular important structure is a kagome lattice with its potentially diverse and vibrant physics. We report a van-der-Waals kagome lattice material, PdPS with several unique properties such as an intriguing flat band.

View Article and Find Full Text PDF
Article Synopsis
  • An exciton is a bosonic quasiparticle formed from electron-hole pairs and has potential for Bose-Einstein condensation in various materials.
  • Recent findings show a spin-orbit-entangled exciton state in the antiferromagnetic van der Waals material NiPS below 150 kelvin, which is linked to many-body states like the Zhang-Rice singlet.
  • Utilizing three spectroscopy methods, researchers confirmed this exciton has a very narrow linewidth below 50 kelvin, suggesting that van der Waals magnets could be valuable for researching coherent many-body excitons.
View Article and Find Full Text PDF

Emergent phenomena driven by electronic reconstructions in oxide heterostructures have been intensively discussed. However, the role of these phenomena in shaping the electronic properties in van der Waals heterointerfaces has hitherto not been established. By reducing the material thickness and forming a heterointerface, we find two types of charge-ordering transitions in monolayer VSe on graphene substrates.

View Article and Find Full Text PDF

Most interesting phenomena of condensed matter physics originate from interactions among different degrees of freedom, making it a very intriguing yet challenging question how certain ground states emerge from only a limited number of atoms in assembly. This is especially the case for strongly correlated electron systems with overwhelming complexity. The Verwey transition of FeO is a classic example of this category, of which the origin is still elusive 80 years after the first report.

View Article and Find Full Text PDF

Hexagonal RMnO is a multiferroic compound with a giant spin-lattice coupling at an antiferromagnetic transition temperature, Lee et al (2008 Nature 451 805). Despite extensive studies over the past two decades, the origin and underlying microscopic mechanism of strong spin-lattice coupling remain very much elusive. In this study, we have tried to address this problem by measuring the thermal expansion and dielectric constant of doped single crystals Y Lu MnO where x  =  0, 0.

View Article and Find Full Text PDF

Magnetism in two-dimensional materials is not only of fundamental scientific interest but also a promising candidate for numerous applications. However, studies so far, especially the experimental ones, have been mostly limited to the magnetism arising from defects, vacancies, edges, or chemical dopants which are all extrinsic effects. Here, we report on the observation of intrinsic antiferromagnetic ordering in the two-dimensional limit.

View Article and Find Full Text PDF

The range of mechanically cleavable Van der Waals crystals covers materials with diverse physical and chemical properties. However, very few of these materials exhibit magnetism or magnetic order, and thus the provision of cleavable magnetic compounds would supply invaluable building blocks for the design of heterostructures assembled from Van der Waals crystals. Here we report the first successful isolation of monolayer and few-layer samples of the compound nickel phosphorus trisulfide (NiPS3) by mechanical exfoliation.

View Article and Find Full Text PDF