A5101868468- Physics of Superconductivity and Magnetism
- Advanced Condensed Matter Physics
- Magnetic and transport properties of perovskites and related materials
- Multiferroics and related materials
- Magnetic properties of thin films
- Iron-based superconductors research
- Ferroelectric and Piezoelectric Materials
- Quantum and electron transport phenomena
- Electronic and Structural Properties of Oxides
- Magneto-Optical Properties and Applications
- Rare-earth and actinide compounds
- Superconductivity in MgB2 and Alloys
- Magnetic Properties and Applications
- Advanced Physical and Chemical Molecular Interactions
- Geophysics and Sensor Technology
- Geophysics and Gravity Measurements
- Theoretical and Computational Physics
- Geological and Geophysical Studies
- Semiconductor materials and devices
- Thermal Expansion and Ionic Conductivity
- Copper Interconnects and Reliability
- Magnetic Field Sensors Techniques
- High-pressure geophysics and materials
- Semiconductor Quantum Structures and Devices
- Pulsars and Gravitational Waves Research
Sun Yat-sen University
2024
National Yang Ming Chiao Tung University
2000-2019
Lawrence Berkeley National Laboratory
2017
National University of Singapore
2007
National Sun Yat-sen University
1997
State University of New York
1993-1996
Stony Brook University
1993-1996
The comprehensive low-temperature specific heat C(T) data identify both an isotropic s-wave and extended order parameters coexisting in a superconducting single crystal FeSe with Tc=8.11 K. gap {\Delta}0=1.33 meV on the hole Fermi sheets {\Delta}={\Delta}e(1+\alpha*cos2_theta) {\Delta}e=1.13 \alpha=0.78 electron sheets. is rather anisotropic but low energy quasiparticle excitations demonstrate no sign of accidental nodes. coefficient \gamma(H) manifesting contribution to C non-linear...
The effect of electron irradiation with energy from 20 to 120 keV on the resistivity, Hall coefficient, and superconducting critical temperature ${\mathit{T}}_{\mathit{c}}$ ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{6+\mathit{x}}$ thin films has been studied. threshold incident electrons for suppression found, displacement oxygen in ${\mathrm{CuO}}_{2}$ planes evaluated as 8.4 eV along c axis. kinetics production in-plane vacancies studied found be governed by athermal...
The low-temperature specific heat $C(T,H)$ of the superconductor ${\mathrm{MgCNi}}_{3}$ has been measured in detail. $\ensuremath{\Delta}C/{\ensuremath{\gamma}}_{n}{T}_{c}=1.97$ is estimated from anomaly at ${T}_{c}.$ At low temperatures, electronic contribution superconducting state follows ${C}_{\mathrm{es}}/{\ensuremath{\gamma}}_{n}{T}_{c}\ensuremath{\approx}7.96\mathrm{exp}(\ensuremath{-}{1.46T}_{c}/T).$ magnetic-field dependence $\ensuremath{\gamma}(H)$ found to be linear with respect...
High-Tc Josephson junctions have been fabricated by direct electron beam writing over YBa2Cu3O7 thin-film microbridges, using scanning transmission microscope (STEM) with an accelerating voltage of 80–120 kV. Annealing at 330–380 K increases Tc and Ic the makes them more stable. In operating range a few degrees below Tc, show 100% magnetic field modulation critical current, microwave-induced Shapiro steps oscillating according to resistively shunted junction (RSJ) model, RSJ current-voltage...
In this work, we have fabricated FePt films with a thickness in the range of 0.1–1μm using combination electrodeposition and postannealing. composition around Fe50Pt50 were formed by onto Si (100) substrates an underlayer Au, Ag, or Cu, subsequently annealed at temperature 200–900°C for 20min. From our x-ray diffraction analysis, L10 phase started to form after annealing 400°C film deposited on Au underlayer. The highest coercivity (10kOe) was found 600°C. When Ag underlayer, high over 15kOe...
Both spin-liquid and magnetically ordered phases of both half-integer integer low-spin quantum magnets are interest, since the magnetic structures found in latter case usually have no classical counterparts. Such a structure was combined experimental theoretical study spin system $\mathrm{Ni}{(\mathrm{NO}}_{3}{)}_{2}$. Our thermodynamic measurements revealed phase with small spontaneous magnetization at ${T}_{\mathrm{C}} = 5.5\phantom{\rule{0.28em}{0ex}}\mathrm{K}$. The saturation about...
We investigated the electronic reconstruction at n-type LaAlO3/SrTiO3 interface with hard x-ray photoelectron spectroscopy (HAXPES) under grazing incidence. By exploiting collapse of evanescent waves and abrupt increase absorption critical incidence angle, our HAXPES study reveals a 2% from Ti4+ to Ti3+ occurring near interface. Such an also extends into SrTiO3 depth about 48 Å (∼12 unit cells) estimated total charge transfer ∼0.24 electrons per two-dimensional cell.
The Mn 3d valence states in single-crystalline TbMnO3 were probed using x-ray absorption spectroscopy and resonant emission (RXES). polarized K-edge spectra show a strong polarization dependence, particularly for the white line region, indicating anisotropic Mn–O bonding within ab plane TbMnO3. RXES data obtained at K edge clearly reveal that unoccupied exhibit relatively delocalized character, stemming from hybridization of with neighboring 4p orbitals. authors demonstrated is able to...
To shed light on the symmetry of superconducting order parameter in ${\mathrm{Na}}_{x}\mathrm{Co}{\mathrm{O}}_{2}∙y{\mathrm{H}}_{2}\mathrm{O}$, Mn doping effects are studied. X-ray absorption spectroscopy verifies that doped impurities occupy Co sites and with a valance close to $+4$. Impurity scattering by is unitary limit that, however, does not lead strong ${T}_{c}$ suppression. This absence impurity inconsistent simple picture sign-changing parameter. Coexistence $s$-wave nodal one...
In strongly correlated oxides, heterostructures provide a powerful route to manipulate the charge, spin, orbital, and lattice degrees of freedom create distinctive functionalities. this work, we have achieved atomically precise interface control in YBa2Cu3O7−x/La0.7Ca0.3MnO3 (YBCO/LCMO) find hidden effective doping. This mechanism is responsible for higher Tc sample with MnO2-terminated than that La0.7Ca0.3O-terminated interface. The also shows larger magnetic moment Mn together lower...
We have measured low-temperature specific heat C(T,H) of La 1.9Sr 0. 1Cu 1-xZn xO (4) ( x = 0, 0.01, and 0.02) in both zero applied magnetic fields. A pronounced dip C/T below 2 K was observed Zn-doped samples, which is absent the nominally clean one. If origin electronic, quasiparticle density states N(E) samples may be depressed a small energy scale E0. The present data can well described by model N(0)+alphaE(1/2), with nonzero N(0) positive alpha. Magnetic fields depress lead to an...