A5062351924- Advanced Condensed Matter Physics
- Topological Materials and Phenomena
- Physics of Superconductivity and Magnetism
- Organic and Molecular Conductors Research
- Electronic and Structural Properties of Oxides
- Iron-based superconductors research
- Rare-earth and actinide compounds
- Advanced Chemical Physics Studies
- Inorganic Chemistry and Materials
- 2D Materials and Applications
- Quantum and electron transport phenomena
- Magnetic properties of thin films
- Quantum, superfluid, helium dynamics
- Graphene research and applications
- Solid-state spectroscopy and crystallography
- Magnetic and transport properties of perovskites and related materials
- Diamond and Carbon-based Materials Research
- Molecular Junctions and Nanostructures
- Superconductivity in MgB2 and Alloys
- Magnetic Properties of Alloys
- Acoustic Wave Resonator Technologies
- Crystal Structures and Properties
- Semiconductor Quantum Structures and Devices
- Photonic Crystals and Applications
- Photorefractive and Nonlinear Optics
Chinese Academy of Sciences
2018-2025
University of Chinese Academy of Sciences
2018-2025
Czech Academy of Sciences, Institute of Physics
2019-2025
The University of Tokyo
2022-2024
Joint Institute for Laboratory Astrophysics
2020-2022
Institute of Physics
2018-2022
Shanghai Advanced Research Institute
2022
Deutsches Elektronen-Synchrotron DESY
2022
Fachhochschule Kiel
2022
Kiel University
2022
In crystalline materials, electron-phonon coupling (EPC) is a ubiquitous many-body interaction that drives conventional Bardeen-Cooper-Schrieffer superconductivity. Recently, in new kagome metal $\rm{CsV_3Sb_5}$, superconductivity possibly intertwines with time-reversal and spatial symmetry-breaking orders observed. Density functional theory calculations predicted weak EPC strength,$\lambda$, supporting an unconventional pairing mechanism $\rm{CsV_3Sb_5}$. However, experimental determination...
The interplay of nontrivial topology and superconductivity in condensed matter physics gives rise to exotic phenomena. However, materials are extremely rare where it is possible explore the full details superconducting pairing. Here, we investigate momentum dependence gap distribution a novel Dirac material PdTe. Using high resolution, low temperature photoemission spectroscopy, establish as spin-orbit coupled semimetal with topological Fermi arc crossing level on (010) surface. This...
Ultrashort light pulses can selectively excite charges, spins, and phonons in materials, providing a powerful approach for manipulating their properties. Here we use femtosecond laser to coherently manipulate the electron phonon distributions, couplings, charge-density wave (CDW) material 1T-TaSe2 After exciting with pulse, fast spatial smearing of laser-excited electrons launches coherent lattice breathing mode, which turn modulates temperature. This finding is contrast all previous...
Landau's Fermi liquid theory offers a profound understanding of conduction electrons in metals. However, many strongly correlated materials, including heavy-fermions, cuprates, iron-based superconductors, and nickelates, exhibit non-Fermi (NFL) behavior. A hallmark is the strange metal state, characterized by linear-in-temperature resistivity linear-in-energy single-particle decay rate. Using angle-resolved photoemission spectroscopy measurements, we systematically investigate electron-doped...
Abstract The charge density wave (CDW) state is a ubiquitous ordered phase in condensed matter systems, characterized by periodic modulation of the electronic density. In many CDW materials, superconductivity (SC) emerges close proximity to, or coexists with, phase, offering valuable platform to explore interplay between these two competing orders. ZrTe 3-x Se x family provides an ideal system for investigating this interplay, as both CDW-dominated and superconductivity-dominated end members...
The breaking of time-reversal symmetry (TRS) in the normal state kagome superconductors AV
Abstract The iron-based superconductors (FeSCs) have recently emerged as a promising single-material Majorana platform by hosting isolated zero modes (MZMs) at relatively high temperatures. To further verify its nature and move forward to build topological quantum qubits, it is highly desirable achieve tunability for MZMs on homogeneous FeSCs. Here, with an in-situ strain device, we can controllably create the surface of stoichiometric superconductor LiFeAs altering chemical potential....
Charge density wave (CDW) order is an emergent quantum phase that characterized by periodic lattice distortion and charge modulation, often present near superconducting transitions. Here, we uncover a novel inverted CDW state using femtosecond laser to coherently reverse the star-of-David in 1T-TaSe2. We track signature of this time- angle-resolved photoemission spectroscopy time-dependent functional theory validate it associated with unique arrangement never before realized. The dynamic...
In the recently discovered kagome superconductor AV3Sb5 (A = K, Rb, and Cs), superconductivity is intertwined with an unconventional charge density wave order. Its pairing symmetry remains elusive owing to lack of direct measurement superconducting gap in momentum space. this letter, utilizing laser-based ultra-high-resolution low-temperature angle-resolved photoemission spectroscopy, we observe anisotropic Cooper CsV3Sb5. We detect a highly structure anisotropy over 80% maximum along V-V...
The cuprate superconductors distinguish themselves from the conventional in that a small variation carrier doping can significantly change superconducting transition temperature (T_c), giving rise to dome where pseudogap (ref. 1,2) emerges underdoped region and Fermi liquid appears overdoped region. Thus systematic study of properties over wide range is critical for understanding mechanism. Here, we report new technique continuously dope surface Bi2Sr2CaCu2O8+x through an ozone/vacuum...
We have investigated the temporal evolution and fluence dependence of band structure in Ta2Ni0.9Co0.1Se5 by means time- angle-resolved photoemission spectroscopy (tr-ARPES). With 3.00 mJ cm−2 delay time 170 fs, conduction crossing Fermi level (EF) valence reaching EF are observed indicating photoinduced semimetal phase. However, at 70 top does not reach creating a partial gap or pseudogap, transition from excitonic insulator state to is completed. The even with shorter (down 50–70 fs) and/or...
We describe a setup for time- and angle-resolved photoemission spectroscopy with wavelength-tunable excitation an extreme ultraviolet probe. It is enabled by using the 10 kHz twin Ti:sapphire amplifiers seeded common oscillator. The typical probe energy 21.7 eV, wavelength of pump tuned between 2400 1200 nm optical parametric amplifier. spectral width 53 meV, time resolution dependent on pump, better than 60 fs >0.7 eV. This system enables to be matched specific interband transition...
Spin-helical Dirac Fermions at a doped topological insulator's boundaries can support Majorana quasiparticles when coupled with s-wave superconductors, but in n-doped systems, the requisite induced Cooper pairing states is often buried heterointerfaces or complicated by degenerate coupling bulk conduction carriers. Rarely probed are p-doped structures nondegenerate and valence bands Fermi level, which may foster long-range superconductivity without sacrificing physics. Using...
We study the systematic doping evolution of nodal dispersions by in situ angle-resolved photoemission spectroscopy on continuously doped surface a high-temperature superconductor ${\mathrm{Bi}}_{2}{\mathrm{Sr}}_{2}{\mathrm{CaCu}}_{2}{\mathrm{O}}_{8+x}$ and reveal that dispersion has three fundamentally different segments separated two kinks, located at \ensuremath{\sim}10 meV roughly 70 meV, respectively. These have band velocities dependence. In particular, underdoped region velocity...
We utilize high-resolution resonant angle-resolved photoemission spectroscopy (ARPES) to study the band structure and hybridization effect of heavy-fermion compound Ce 2 IrIn 8 . observe a nearly flat at binding energy 7 meV below coherent temperature <?CDATA ${T}_{\mathrm{coh}}\sim 40\,{\rm{K}}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>T</mml:mi> </mml:mrow> <mml:mi>coh</mml:mi> </mml:msub> <mml:mo>∼</mml:mo>...
Abstract The newly discovered kagome superconductors represent a promising platform for investigating the quantum interplay between band topology, electronic order, and lattice geometry. Despite extensive research efforts on this system, nature of superconducting ground state remains elusive. In particular, consensus electron pairing symmetry has not been achieved so far, in part owing to lack momentum-resolved measurement gap structure. Here we report direct observation nodeless, nearly...
We present a phenomenological Green's function to characterize the superconducting and pseudogap phases of cuprates based on microscopic theory doped Mott insulators. In this framework, “Fermi-arc” “kink” phenomena observed by angle-resolved photoemission spectroscopy experiments in phase can be systematically explained as doping, which are further connected two-gap feature with dichotomy between nodal antinodal physics. demonstrate that phase-string-induced fractionalization plays key role...
Abstract Angle-resolved photoemission spectroscopy (ARPES) measurements have established the phenomenon of kink in band dispersion high- T c cuprate superconductors. However, systematic studies electron-doped cuprates are still lacking experimentally. We performed situ ARPES on La 2− x Ce CuO 4±δ (LCCO) thin films over a wide electron doping ( n ) range from 0.05 to 0.23. While nodal is nearly invisible, an antinodal around 45 meV, surviving above 200 K, observed for ~ 0.05–0.19, whose...
In crystalline materials, electron-phonon coupling (EPC) is a ubiquitous many-body interaction that drives conventional Bardeen-Cooper-Schrieffer superconductivity. Recently, in new kagome metal $\rm{CsV_3Sb_5}$, superconductivity possibly intertwines with time-reversal and spatial symmetry-breaking orders observed. Density functional theory calculations predicted weak EPC strength,$λ$, supporting an unconventional pairing mechanism $\rm{CsV_3Sb_5}$. However, experimental determination of...
The newly discovered kagome superconductors represent a promising platform for investigating the interplay between band topology, electronic order, and lattice geometry. Despite extensive research efforts on this system, nature of superconducting ground state remains elusive. In particular, consensus electron pairing symmetry has not been achieved so far, in part owing to lack momentum-resolved measurement gap structure. Here we report direct observation nodeless, nearly isotropic,...