A5089759390- Physics of Superconductivity and Magnetism
- Advanced Condensed Matter Physics
- Inorganic Chemistry and Materials
- Iron-based superconductors research
- Crystal Structures and Properties
- Topological Materials and Phenomena
- Magnetic and transport properties of perovskites and related materials
- Magnetic properties of thin films
- Inorganic Fluorides and Related Compounds
- Multiferroics and related materials
- Surface and Thin Film Phenomena
- Rare-earth and actinide compounds
- Mesoporous Materials and Catalysis
- Iron oxide chemistry and applications
- Metalloenzymes and iron-sulfur proteins
- Ammonia Synthesis and Nitrogen Reduction
- Gestational Trophoblastic Disease Studies
- Peptidase Inhibition and Analysis
- Amyloidosis: Diagnosis, Treatment, Outcomes
- Nanomaterials for catalytic reactions
- High-pressure geophysics and materials
- Advanced Chemical Physics Studies
- Theoretical and Computational Physics
- Parathyroid Disorders and Treatments
- Advanced Measurement and Detection Methods
SLAC National Accelerator Laboratory
2020-2025
Stanford University
2018-2025
Xi'an University of Science and Technology
2018
Ordnance Engineering College
2011
Hefei University of Technology
2006
Shandong Institute of Automation
2006
Guizhou University
2006
A sharp boundary in the cuprates Many physicists working on cuprate superconductors believe that so-called strange metal phase diagram is associated with a quantum critical point. Within this picture, point gives rise to V-shaped region doping-temperature of cuprates: phase. Chen et al. used angle-resolved photoemission spectroscopy family Bi2212 challenge view. By taking comprehensive measurements as function doping and temperature—and making sure signal was not affected by environmental...
Significance Fermi surface (FS) topology is a fundamental property of metals and superconductors. In electron-doped cuprate Nd 2− x Ce CuO 4 , an unexpected FS reconstruction has been observed in optimal- overdoped regime ( = 0.15 − 0.17) by quantum oscillation measurements (QOM). This puzzling because neutron scattering suggests that the antiferromagnetic long-range order, which believed to reconstruct FS, vanishes before 0.14. Here, we report angle-resolved photoemission evidence...
The effect of Lifshitz transition on thermodynamics and superconductivity in hole-doped cuprates has been heavily debated but remains an open question. In particular, observed peak electronic specific heat is proposed to originate from fluctuations a putative quantum critical point p* (e.g., the termination pseudogap at zero temperature), which close distinguishable overdoped La-based where Fermi surface transforms hole-like electron-like. Here we report situ angle-resolved photoemission...
Measurements of the thermal Hall conductivity in hole-doped cuprates have shown that phonons acquire chirality a magnetic field both pseudogap phase and Mott insulator state. The microscopic mechanism at play is still unclear. A number theoretical proposals are being considered including skew scattering by various defects, coupling to spins, state loop-current order with appropriate symmetries, but more experimental information required constrain scenarios. Here we present our study...
Recent studies of La_{3}Ni_{2}O_{7} have identified a bilayer (2222) structure and an unexpected alternating monolayer-trilayer (1313) structure, both which feature signatures superconductivity near 80 K under high pressures. Using angle-resolved photoemission spectroscopy, we measure the electronic 1313 samples. In contrast to previously studied 2222 find that hosts flat band with markedly different binding energy, as well additional electron pocket splittings. By comparison local-density...
Accurately estimating the state of charge (SOC) power batteries in electric vehicles is great significance to measurement endurance mileage vehicles, as well safety protection battery. In view lithium ion batteries’ nonlinear relation between SOC estimation and current, voltage, temperature, improved Back Propagation (BP) neural network method proposed accurately estimate batteries. To address inherent limitations BP network, particle swarm algorithm adopted modify relevant weighting...
In the underdoped n-type cuprate Nd
Significance The correlation-driven topological insulator is a poorly understood state of matter where protection afforded in the absence well-defined quasiparticles. Ongoing research hampered by scarcity model material families, consisting only 4f rare-earth boride compounds thus far. Here we establish class candidate Kondo FeSb 2 , based on 3d electrons instead electrons. Comparison between different families will allow identification key ingredients responsible for exotic insulating...
Signatures of superconductivity near 80 K were recently discovered in crystals La-Ni-O with the stoichiometry 3:2:7 under high pressures. Structural studies have shown conflicting results highlighting both expected bilayer (2222) structure and an unexpected alternating monolayer-trilayer (1313) structure, apparently showing superconductivity. Here, we perform angle-resolved photoemission spectroscopy on 1313 to elucidate distinct electronic features compared previously studied 2222...
A surprising “planar” thermal Hall effect, whereby the field is parallel to current, has recently been observed in a few magnetic insulators; this effect attributed exotic excitations such as Majorana fermions or chiral magnons. Here, we investigate possibility of planar three different cuprate materials, which conventional conductivity <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:msub><a:mi>κ</a:mi><a:mi>xy</a:mi></a:msub></a:math> (with an out-of-plane...
Here we report that TiSe2 thin films can be epitaxially grown on TiO2 substrates despite different lattice symmetry between the two materials. The prepared via molecular beam epitaxy (MBE) in ways: by conventional co-deposition using selenium and titanium sources, evaporating just reconstructed surfaces of TiO2. Both growth methods yield crystalline with similar electronic band structures. exhibit large electron doping a lack charge density wave (CDW) order, which is from both bulk single...
Time- and angle-resolved photoemission spectroscopy is a powerful probe of electronic band structures out equilibrium. Tuning time energy resolution to suit particular scientific question has become an increasingly important experimental consideration. Many instruments use cascaded frequency doubling in nonlinear crystals generate the required ultraviolet pulses. We demonstrate how calculations clarify relationship between laser bandwidth crystal thickness contributing resolutions place...
In contrast to hole-doped cuprates, electron-doped cuprates consistently exhibit strong antiferromagnetic correlations with a commensurate ({\pi}, {\pi}) ordering wave vector, leading the prevalent belief that spin fluctuations mediate Cooper pairing in these unconventional superconductors. However, early investigations produced two paradoxical findings: while create largest pseudogap at "hot spots" momentum space, Raman scattering and angle-resolved photoemission spectroscopy measurements...
A surprising "planar" thermal Hall effect, whereby the field is parallel to current, has recently been observed in a few magnetic insulators, and this attributed exotic excitations such as Majorana fermions or chiral magnons. Here we investigate possibility of planar effect three different cuprate materials, which conventional conductivity $\kappa_{\rm {xy}}$ (with an out-of-plane perpendicular current) dominated by either electrons phonons. Our measurements show that from cuprates zero,...
We present local and nonlocal electrical transport measurements of the correlated insulator FeSb$_2$. By employing wiring configurations that delineate between bulk- surface-dominated conduction, we reveal formation a metallic surface state in FeSb$_2$ for temperatures $\lessapprox 5$~K. This result is corroborated by an angular rotation study this material's magnetotransport, which also shows signatures transition from to conduction over same temperature interval as local/nonlocal...
Spin- and charge-lattice interactions are potential key factors in the microscopic mechanism of high-temperature superconductivity cuprates. Although both can dramatically shape low-energy electronic structure, their phenomenological roles usually investigated independently. Employing angle-resolved photoemission spectroscopy, we reveal spectroscopic fingerprint short-range antiferromagnetic order conjunction with enhanced electron-phonon interaction electron-doped cuprate superconductor...
It has recently become clear that phonons generate a sizable thermal Hall effect in cuprates, whether they are undoped, electron-doped or hole-doped (inside the pseudogap phase). At higher doping, where cuprates reasonably good metals, mobile electrons also effect, equivalent of standard electrical effect. Here we show cleanest crystals cuprate Nd$_{2-x}$Ce$_{x}$CuO$_{4}$, at high phonon and electron contributions to conductivity $\kappa_{\rm {xy}}$ comparable magnitude, but opposite sign....
Since the interaction between magnetic field and fluid is complicated, signal models of electromagnetic flowmeter under sinewave excitation cannot describe accurately relationship among sensor output, flow rate, exciting now. The multiple regression method adopted to build based on experimental data in this article. not only express action rate but also reflect effects transformer eddy current.
In the underdoped n-type cuprate Nd2-xCexCuO4, long-ranged antiferromagnetic order reconstructs Fermi surface, resulting in a putative metal with small pockets. Using angle-resolved photoemission spectroscopy, we observe an anomalous energy gap, of magnitude smaller than wide range regime and smoothly connecting to superconducting gap at optimal doping. After carefully considering all known ordering tendencies tandem phase diagram, hypothesize that normal state cuprates originates from...