A5074056521- Muon and positron interactions and applications
- Physics of Superconductivity and Magnetism
- Advanced Condensed Matter Physics
- Rare-earth and actinide compounds
- Iron-based superconductors research
- Magnetic and transport properties of perovskites and related materials
- Superconducting Materials and Applications
- Superconductivity in MgB2 and Alloys
- Particle accelerators and beam dynamics
- Advanced NMR Techniques and Applications
- Ammonia Synthesis and Nitrogen Reduction
- Graphene research and applications
- Advancements in Battery Materials
- Multiferroics and related materials
- Particle Detector Development and Performance
- ZnO doping and properties
- Particle physics theoretical and experimental studies
- Magnetic Properties of Alloys
- High-Energy Particle Collisions Research
- Atomic and Molecular Physics
- Solid-state spectroscopy and crystallography
- Theoretical and Computational Physics
- Magnetic properties of thin films
- Inorganic Fluorides and Related Compounds
- Nuclear Physics and Applications
High Energy Accelerator Research Organization
2016-2025
The Graduate University for Advanced Studies, SOKENDAI
2016-2025
Tokyo Institute of Technology
2019-2025
Institute of Materials Structure Science
2006-2024
Institute of Materials Science
2024
Japan Proton Accelerator Research Complex
2012-2023
Nippon Soken (Japan)
2020
Guangdong Technion-Israel Institute of Technology
2019
Japan Atomic Energy Agency
2019
University of Wollongong
2019
The muon-spin-relaxation rate $\ensuremath{\sigma}$ has been measured in sixteen specimens of high-${T}_{c}$ cuprate superconductors (the 2:1:4, 1:2:3, 2:2:1:2, and 2:2:2:3 series). This allowed us to study the magnetic field penetration depth $\ensuremath{\lambda}$ thus superconducting carrier density ${n}_{s}$ divided by effective mass ${m}^{*}(\ensuremath{\sigma}\ensuremath{\propto}\frac{1}{{\ensuremath{\lambda}}^{2}}\ensuremath{\propto}\frac{{n}_{s}}{{m}^{*}})$. A universal linear...
This paper introduces a new approach to measure the muon magnetic moment anomaly |$a_{\mu} = (g-2)/2$| and electric dipole (EDM) |$d_{\mu}$| at J-PARC facility. The goal of our experiment is |$a_{\mu}$| using an independent method with factor 10 lower momentum, 20 smaller diameter storage-ring solenoid compared previous ongoing |$g-2$| experiments unprecedented quality storage field. Additional significant differences from present experimental include 1000 transverse emittance beam...
The magnetic ground state of single crystalline RuO_{2} was investigated by the muon spin rotation and relaxation (μSR) experiment. precession signal due to spontaneous internal field B_{loc}, which is expected in magnetically ordered phase, not observed temperature range 5-400 K. Muon sites were evaluated first-principles calculations using dilute hydrogen simulating as pseudohydrogen, B_{loc} simulated for antiferromagnetic structures with a Ru moment |m_{Ru}|≈0.05μ_{B} suggested from...
We report on muon-spin relaxation measurements of the 4f(2)-based heavy-fermion superconductor filled-skutterudite Pr(Os4Sb12. The results reveal spontaneous appearance static internal magnetic fields below superconducting transition temperature, providing unambiguous evidence for breaking time-reversal symmetry in state. A discussion is made which spin or orbital component Cooper pairs carries a nonzero momentum.
We report muon spin relaxation and rotation measurements on sintered ceramic samples of ${\mathrm{Nd}}_{2\mathrm{\ensuremath{-}}\mathit{x}}$${\mathrm{Ce}}_{\mathit{x}}$${\mathrm{CuO}}_{4\mathrm{\ensuremath{-}}\mathit{y}}$ a large single crystal ${\mathrm{Nd}}_{2}$${\mathrm{CuO}}_{4\mathrm{\ensuremath{-}}\mathit{y}}$. find an electronic phase diagram that is quite similar to hole-doped superconductors such as...
The magnetic properties of PbVO3, a PbTiO3-type perovskite with large tetragonal distortion (c/a = 1.229), were investigated. temperature dependence the measured magnetization multidomain single-crystal samples showed broad maximum centered around 180 K, indicating two-dimensional antiferromagnetism. μSR measurement revealed presence long-range order below 43 K. magnetism is due to ordering dxy orbitals, which thought also be related PbVO3.
A layered iridate Ba${}_{2}$IrO${}_{4}$ was synthesized using a high-pressure synthesis technique. Its electronic state studied through electrical resistivity, magnetic susceptibility, and \ensuremath{\mu}SR experiments. It found that crystallizes in ${\mathrm{K}}_{2}$NiF${}_{4}$-type structure (space group $I$4/mmm) with lattice parameters $a$ $=$4.030(1) \AA{} $c$ $=$13.333(4) \AA{}. The includes flat IrO${}_{2}$ square planar lattices straight Ir-O-Ir bonds. is Mott insulator (activation...
Several recent models of high-${\mathit{T}}_{\mathit{c}}$ superconductivity predict static internal magnetic fields along the c axis due to spontaneously broken parity and time-reversal symmetries. Muon spin relaxation has been used study in c-axis-oriented samples sintered ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7}$ thick-film ${\mathrm{Bi}}_{2}$${\mathrm{Sr}}_{2}$${\mathrm{CaCu}}_{2}$${\mathrm{O}}_{8}$. The magnitude, anisotropy, temperature dependence observed favor a...
The electronic structure and the location of muonium centers (Mu) in single-crystalline ZnO were determined for first time. Two species Mu with extremely small hyperfine parameters have been observed below 40 K. Both an axial-symmetric along a $⟨0001⟩$ axis, indicating that they are located at antibonding (${\mathrm{A}\mathrm{B}}_{\mathrm{O},\ensuremath{\parallel}}$) bond-center (${\mathrm{B}\mathrm{C}}_{\ensuremath{\parallel}}$) sites. It is inferred from their ionization energy...
Internal magnetic fields in ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{\mathrm{x}}$ and ${\mathrm{La}}_{1.85}$${\mathrm{Sr}}_{0.15}$${\mathrm{CuO}}_{4}$ have been investigated below 90 mK using muon spin rotation. In the static internal field at site due to ordering remains constant with increasing x up until x=6.30 then rapidly approaches zero just above x=6.44. heavily doped samples of (x\ensuremath{\ge}6.54, ${T}_{c}$\ensuremath{\ge}52 K)...
The diffusion rate of muonium in an insulator, KCl, has been determined from measurements muon spin relaxation induced by motion the presence nuclear hyperfine interactions. crossover stochastic to coherent hopping occurs at about 70 K, as evidenced a dramatic rise hop lower temperatures. rises much more rapidly with decreasing temperature than for metals, predicted current theories on light interstitials absence conduction electrons.
We have measured the magnetic penetration depth of high-${\mathit{T}}_{\mathit{c}}$ superconducting system ${\mathrm{Y}}_{1\mathrm{\ensuremath{-}}\mathit{x}}$${\mathrm{Pr}}_{\mathit{x}}$${\mathrm{Ba}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{6.97}$ for 0.05\ensuremath{\le}x\ensuremath{\le}0.4 using technique transverse-field muon-spin relaxation. The temperature dependence is similar to that related compounds...
The diffusion of positive muons (${\ensuremath{\mu}}^{+}$\ensuremath{\approxeq}0.11\ifmmode\times\else\texttimes\fi{}proton mass) in copper was studied experimentally by the zero-field muon-spin-relaxation method a temperature (T) range from 70 mK to 190 K, using pulsed muon beam suitable for present method. measurements were performed three samples different purities see effect impurities on nature ${\ensuremath{\mu}}^{+}$ diffusion. We find that (hopping) rate \ensuremath{\nu} ultrapure...
A complex structure of the superconducting order parameter in $L{n}_{2}{\mathrm{C}}_{3}$ ($Ln=\mathrm{La},\mathrm{Y}$) is demonstrated by muon spin relaxation measurements their mixed state. The depolarization rate [${\ensuremath{\sigma}}_{v}(T)$] exhibits a characteristic temperature dependence that can be perfectly described phenomenological double-gap model for nodeless superconductivity. While magnitude two gaps similar between ${\mathrm{La}}_{2}{\mathrm{C}}_{3}$ and...
A muon experimental facility, known as the Muon Science Establishment (MUSE), is one of user facilities at Japan Proton Accelerator Research Complex, along with those for neutrons, hadrons, and neutrinos. The MUSE facility integrated into Materials Life Facility building in which a high-energy proton beam that shared neutron experiment delivers variety beams research covering diverse scientific fields. In this review, we present current status MUSE, still process being developed its fully...
We propose a model to describe the fluctuations in internal magnetic field due ion dynamics observed muon spin relaxation (μSR) by an Edwards–Anderson-type autocorrelation function that separates quasi-static and dynamic components of correlation parameter Q (where 0 ≤ 1). Our Monte Carlo simulations for this showed time evolution polarization deviates significantly from Kubo–Toyabe function. To further validate model, results were compared with μSR spectra hybrid organic–inorganic...
It is demonstrated by muon spin relaxation and resonance experiments that the switchable spontaneous polarization of organic ferroelectric compound tris(4-acetylphenyl)amine governed local molecular dynamics acetyl group. The implanted forms paramagnetic states, which exhibit longitudinal due to fluctuation hyperfine fields exerted from unpaired electrons. first-principle density functional theory calculations indicate these states are muonated radicals localized at phenyl group on...
We have performed $^{69,71}$Ga nuclear magnetic resonance (NMR) and quadrupole (NQR) muon spin rotation/resonance on the quasi two-dimensional antiferromagnet (AFM) NiGa$_2$S$_4$, in order to investigate its dynamics state at low temperatures. Although there exists only one crystallographic site for Ga we found two distinct signals by NMR NQR. The origin of is not fully understood, but possibly due stacking faults along c axis which induce additional broad NQR with different local...
We have studied the quantum diffusion of positive muons in pure copper over temperature range 12 mK\ensuremath{\le}T\ensuremath{\le}150 K using technique muon-spin relaxation. The rate has been deduced from its effect upon muon-polarization function. measurements were made a weak longitudinal external magnetic field, where spin relaxation proved to be most sensitive muon hop below 150 K. Our results for behavior are well explained by recently developed theories light interstitials metals...