A5088427323- Iron-based superconductors research
- Advanced Condensed Matter Physics
- Magnetic and transport properties of perovskites and related materials
- Rare-earth and actinide compounds
- High-pressure geophysics and materials
- Physics of Superconductivity and Magnetism
- Multiferroics and related materials
- Perovskite Materials and Applications
- Crystal Structures and Properties
- Quantum Dots Synthesis And Properties
- Chalcogenide Semiconductor Thin Films
- Geomagnetism and Paleomagnetism Studies
- Superconductivity in MgB2 and Alloys
- Organic and Molecular Conductors Research
- Catalysis and Oxidation Reactions
- Inorganic Fluorides and Related Compounds
- X-ray Diffraction in Crystallography
- Magnetism in coordination complexes
- Clostridium difficile and Clostridium perfringens research
- Crystallography and Radiation Phenomena
- Dialysis and Renal Disease Management
- 2D Materials and Applications
- Advanced Materials Characterization Techniques
- Inorganic Chemistry and Materials
- Enzyme Structure and Function
Cornell University
2014-2021
Institute for Basic Science
2018-2021
Oak Ridge National Laboratory
2017-2018
Korea Advanced Institute of Science and Technology
2017
Quantum Science Center
2017
University of Virginia
2012-2013
In a photovoltaic perovskite, entropy-driven structural transition enables kinetic trapping of desired phase.
Significance Hybrid organic–inorganic perovskites (HOIPs) are among the most promising materials for next-generation solar cells that combine high efficiency and low cost. The record of HOIP-based has reached above 22%, which is comparable to silicon cells. HOIP can be manufactured using simple solution processing methods drastically cheaper than current commercial cell technologies. Despite progress so far, microscopic mechanism in HOIPs yet understood. Our study shows rotation organic...
The Spallation Neutron Source at Oak Ridge National Laboratory, USA, ushered in a new era of neutron scattering experiments through the use event-based data. Tagging each event allows pump–probe experiments, measurements with parameter asynchronous to source, continuously varying parameters and novel ways testing instrument components. This contribution will focus on few examples. A pulsed magnet has been used study diffraction under extreme fields. Continuous ramping temperature is becoming...
Using pulsed magnetic fields up to $30\phantom{\rule{0.28em}{0ex}}\mathrm{T}$ we have measured the bulk magnetization and electrical polarization of ${\mathrm{LiNiPO}}_{4}$ studied its structure by time-of-flight neutron Laue diffraction. Our data establish existence a reentrant magnetoelectric phase between $19\phantom{\rule{0.28em}{0ex}}\mathrm{T}$ $21\phantom{\rule{0.28em}{0ex}}\mathrm{T}$. We show that magnetized version zero field commensurate explains response quantitatively. The...
Using single-crystal neutron and x-ray diffraction, we discovered a charge density wave (CDW) below 320 K, which accounts for the long-sought origin of heat capacity resistivity anomalies in ${\mathrm{UPt}}_{2}{\mathrm{Si}}_{2}$. The modulation vector, ${\mathbit{Q}}_{\mathrm{mod}}$, is intriguingly similar to incommensurate vector ${\mathrm{URu}}_{2}{\mathrm{Si}}_{2}$. ${\mathbit{Q}}_{\mathrm{mod}}$ shows an unusual temperature dependence, shifting from commensurate position upon cooling...
The duality between localized and itinerant nature of magnetism in $5\textit{f}$ electron systems has been a longstanding puzzle. Here, we report inelastic neutron scattering measurements, which reveal both local aspects single crystalline system UPt$_{2}$Si$_{2}$. In the antiferromagnetic state, observe broad continuum diffuse magnetic with resonance-like gap $\approx$ 7 meV, surprising absence coherent spin-waves, suggestive magnetism. While closes above Neel temperature, strong dynamic...
We report the observation of a two-dimensional (2D) checkerboard charge density wave (CDW) in low-dimensional superconductor Ta4Pd3Te16. By determining its CDW properties across temperature-pressure (T−P) phase diagram and comparing with prototypical materials, we conclude that Ta4Pd3Te16 features (a) an incommensurate mixed character dimensions [quasi-1D (Q1D) considering needlelike shape along b axis, Q2D as has vectors, 3D because projections all three axes], (b) one weakest CDWs compared...
We investigate the imaginary part of wave vector dependent dynamic spin susceptibility in Sr$_2$(Ru$_{0.99}$Ti$_{0.01}$)O$_4$ as a function temperature using neutron scattering. At T=5 K, two-dimensional incommensurate (IC) magnetic fluctuations are clearly observed around $\mathbf{Q}_\text{c}=(0.3,0.3,L)$ up to approximately 60 meV energy transfer. find that IC excitations disperse ridges $(\pi,\pi)$ point. Below 50 and well described by phenomenological response for Fermi liquid system...
The nature of superconductivity in ${\mathrm{BiS}}_{2}$-based superconductors has been controversial while ab initio calculations proposed this system close proximity to a charge-density-wave (CDW) phase. Using high-energy high-flux x-ray diffraction, we reveal an intrinsic and long-range CDW phase coexisting with ${\mathrm{NdO}}_{1\ensuremath{-}x}{\mathrm{F}}_{x}{\mathrm{BiS}}_{2}$ superconductor $(x=0.37 \mathrm{and} 0.3)$. wave vector...
The simultaneous occurrence of the structural and magnetic phase transitions observed in MnV2O4 is one clear example strong interplay among spin, orbital lattice degrees freedom. structure switched by field linear magnetostriction very high. order mediates interaction between spin generating these phenomena. In this work, we present experimental evidence an its reorientation under a rotating as obtained nuclear resonance(NMR). shift resonance frequency V NMR spectrum symmetrical with respect...
Using high-energy-resolution inelastic x-ray scattering, we observe anomalous softening and damping of the transverse acoustic phonon in UPt$_2$Si$_2$ as system is cooled towards charge density wave (CDW) transition temperature, T$_{\rm{CDW}}$. The exhibits a marked Kohn type anomaly around CDW vector, Q$_{\rm CDW}$, becomes over-damped within finite momentum range already well above dispersion consistent with potential Fermi surface nesting, which together extended collapse indicate strong...
Abstract High temperature crystal structure of UPt 2 Si determined using single-crystal neutron diffraction at 400 K is reported. It found that the remains primitive tetragonal CaBe Ge type with space group P 4/ nmm . Anisotropic displacement factors Pt atoms a (3/4 1/4 0) and c (1/4 z ) Wyckoff sites are to be anomalously large.
Background: The gut microbiome may play a role in the regulation of immune system and infectious complications, its association with kidney transplantation outcomes merits evaluation. Methods: We prospectively enrolled 26 transplant recipients collected serial fecal specimens (n=85) during first 3 months transplantation. Using 16S rRNA deep sequencing, we examined bacterial composition 85 whether microbial community changed following alterations were associated acute rejection (AR) and/or...
Background: BKV nephropathy is not only associated with increased risk of proximate graft loss but also a significantly shortened survival compared to those who did develop BKVN (KI 2005, vol 68 p1834). The basis for this progressive decline despite clearance viremia/nephropathy clear. We have previously reported that heightened expression mRNAs fibrosis at the time predicts subsequent renal allograft loss. Herein we explored changes in urinary cell mRNA profiles following and BK viremia....