papers

Publications (21)

cond-mat.mtrl-sci2015

Magnetic field-induced insulator-semimetal transition in a pyrochlore Nd2Ir2O7

K. Ueda, J. Fujioka, B. -J. Yang +6

We have investigated magneto-transport properties in a single crystal of pyrochore-type Nd2Ir2O7. The metallic conduction is observed on the antiferromagnetic domain walls of the a…

cond-mat.stat-mech2009

Cu- and Cl-NMR Studies of Triplet Localization in the Quantum Spin System NHCuCl

H. Inoue, S. Tani, S. Hosoya +12

Cu- and Cl-NMR experiments were performed to investigate triplet localization in the dimer compound NHCuCl, which shows magnetization plateaus a…

cond-mat.supr-con2006

Improved critical current densities in MgB2 tapes with ZrB2 doping

Xianping Zhang, Zhaoshun Gao, Dongliang Wang +4

MgB2/Fe tapes with 2.5-15 at.% ZrB2 additions were prepared through the in situ powder-in-tube method. Compared to the pure tape, a significant improvement in the in-field critical…

cond-mat.supr-con2006

Large irreversibility field in nanoscale C-doped MgB2/Fe tape conductors

Yanwei Ma, Xianping Zhang, S. Awaji +5

We investigated the effect of nanoscale-C doping on the critical current density Jc and irreversibility field Birr of Fe-sheathed MgB2 tapes prepared by the in-situ powder-in-tube…

cond-mat.mes-hall2011

Insulating phase of a two-dimensional electron gas in MgZnO/ZnO heterostructure below nu = 1/3

Y. Kozuka, A. Tsukazaki, D. Maryenko +7

We report magnetotransport properties of a two-dimensional electron gas confined at MgZnO/ZnO heterointerface in a high magnetic field up to 26 T. High electron mobility and low ch…

cond-mat.str-el2017

Quantum Hall effect in a bulk antiferromagnet EuMnBi with magnetically confined two-dimensional Dirac fermions

H. Masuda, H. Sakai, M. Tokunaga +11

For the innovation of spintronic technologies, Dirac materials, in which the low-energy excitation is described as relativistic Dirac fermions, are one of the most promising system…

cond-mat.supr-con2022

Field Induced Multiple Superconducting Phases in UTe2 along Hard Magnetic Axis

H. Sakai, Y. Tokiwa, P. Opletal +7

The superconducting (SC) phase diagram in uranium ditelluride is explored under magnetic fields () along the hard magnetic b-axis using a high-quality single crystal with $T_{\r…

cond-mat.supr-con2006

Enhanced critical current density of MgB2 superconductor synthesized in high magnetic fields

Yanwei Ma, Aixia Xu, Xianping Zhang +3

The effect of high magnetic fields on the current carrying properties of both MgB2 bulks and Fe-sheathed tapes was investigated following different thermal sequences. It is found t…

cond-mat.supr-con2025

Self-reconstruction of order parameter in spin-triplet superconductor UTe

Y. Tokiwa, P. Opletal, H. Sakai +10

We investigate the effect of easy-axis metamagnetic crossover on superconductivity in UTe along the -axis through measurements of AC susceptibility, magnetization, and the m…

cond-mat.str-el2023

Anomalous vortex dynamics in spin-triplet superconductor UTe

Y. Tokiwa, H. Sakai. S. Kambe, P. Opletal +7

The vortex dynamics in the spin-triplet superconductor, UTe, are studied by measuring the DC electrical resistivity with currents along the -axis under magnetic fields along…

cond-mat.supr-con2014

Numerical evaluation of AC losses in an HTS insert coil for high field magnet during its energization

K. Kajikawa, S. Awaji, K. Watanabe

AC losses in a high temperature superconducting (HTS) insert coil for a 25-T cryogen-free superconducting magnet are numerically calculated during its energization, assuming slab a…

cond-mat.str-el2007

NMR Study on the Vortex Slush Phase in Organic Superconductor κ-(BEDT-TTF)2Cu(NCS)2

M. Urano, J. Tonishi, H. Inoue +10

The vortex state in a single crystal of the layered organic superconductor κ-(BEDT-TTF2Cu(NCS)2, where BEDT-TTF (or ET) is bis(ethylenedithio)tetrathiafulvalene, was studied by 1H…

cond-mat.supr-con2005

Effect of nano-C doping on the in-situ processed MgB2 tapes

Xianping Zhang, Yanwei Ma*, Aixia Xu +6

The effect of nano-C doping on the microstructure and superconducting properties of Fe-sheathed MgB2 tapes prepared through the in-situ powder-in-tube method was studied. Heat trea…

cond-mat.str-el2021

Electric Quadrupolar Contributions in the Magnetic Phases of UNiB

T. Yanagisawa, H. Matsumori, H. Saito +10

We present acoustic signatures of the electric quadrupolar degrees of freedom in the honeycomb-layer compound UNiB. The transverse ultrasonic mode shows softening belo…

cond-mat.str-el2006

Cu-NMR study on the disordered quantum spin magnet with the Bose-glass ground state

T. Fujiwara, H. Inoue, A. Oosawa +9

Cu-NMR study has been performed on the disordered spin-gap system Tl1-xKxCuCl3 In the high-field H > HC=Δ/μ_B, where Δis the spin-gap, the hyperfine field becomes extremely inho…

cond-mat.supr-con2006

Discovery of Li2(Pd,Pt)3B superconductors

P. Badica, K. Togano, H. Takeya +3

Critical temperature Tc of the Li2(Pd1-xPtx)3B was reported to be 7-8K for x=0 and 2.2-2.8K for x=1. In this article we present our preliminary results on behavior of magnetization…

cond-mat.mtrl-sci2020

Magnetic-field-induced topological phase transition in Fe-doped (Bi,Sb)Se heterostructures

Y. Satake, J. Shiogai, G. P. Mazur +9

Three-dimensional topological insulators (3D-TIs) possess a specific topological order of electronic bands, resulting in gapless surface states via bulk-edge correspondence. Exotic…

cond-mat.supr-con2024

Reinforcement of superconductivity by quantum critical fluctuations of metamagnetism in UTe

Y. Tokiwa, . P. Opletal, H. Sakai +8

The normal-conducting state of the superconductor UTe is studied by entropy analysis for magnetic fields along the -axis, obtained from magnetization using the relation $(\p…

cond-mat.mtrl-sci2006

Improved properties of epitaxial YNixMn1-xO3 films by annealing under high magnetic fields

Yanwei Ma, Aixia Xu, Xiaohang Li +4

The effect of annealing under a magnetic field on the microstructure and properties of YNixMn1-xO3 (x=0.33 and 0.5) films has been investigated. It is found that the ferromagnetic…

cond-mat.supr-con2008

A cheap liquid additive from acetone for strong in-field Jc enhancement in MgB2 conductors

Dongliang Wang, Yanwei Ma, Zhaoshun Gao +5

We report on significant flux pinning enhancement in MgB2/Fe tapes that has been easily obtained by a simple and cheap route using acetone as both an efficient ball-milling medium…

cond-mat.supr-con2010

Fabrication and some properties of biaxially aligned Sr0.6K0.4Fe2As2 superconductors by processing in high magnetic field

Zhaoshun Gao, Xianping Zhang, Dongliang Wang +7

We fabricated the c axis and ab-plane biaxially aligned Sr0.6K0.4Fe2As2 superconductor using a two-step magnetic field procedure. The effect of magnetic fields on the structure and…