A5042788719- Graphene research and applications
- Quantum and electron transport phenomena
- 2D Materials and Applications
- Topological Materials and Phenomena
- Electronic and Structural Properties of Oxides
- Molecular Junctions and Nanostructures
- Quantum, superfluid, helium dynamics
- Atomic and Subatomic Physics Research
- Perovskite Materials and Applications
- Mechanical and Optical Resonators
- MXene and MAX Phase Materials
- Surface and Thin Film Phenomena
- Physics of Superconductivity and Magnetism
- Photonic and Optical Devices
- Carbon Nanotubes in Composites
- Force Microscopy Techniques and Applications
- Boron and Carbon Nanomaterials Research
- Advanced Condensed Matter Physics
- Advanced Fluorescence Microscopy Techniques
- Lipid Membrane Structure and Behavior
- Terahertz technology and applications
- Diamond and Carbon-based Materials Research
- Spectroscopy and Quantum Chemical Studies
- Cold Atom Physics and Bose-Einstein Condensates
- Cholangiocarcinoma and Gallbladder Cancer Studies
Shandong University of Science and Technology
2025
University of California, Santa Barbara
2020-2024
State Key Laboratory of Surface Physics
2015-2023
Fudan University
2014-2023
University of Houston
2021-2022
Donostia International Physics Center
2020-2021
Collaborative Innovation Center of Advanced Microstructures
2016-2018
University of Wales
1993
In conventional superconductors, Cooper pairing occurs between electrons of opposite spin. We observe spin-polarized superconductivity in Bernal bilayer graphene when doped to a saddle-point van Hove singularity generated by large applied perpendicular electric field. cascade electrostatic gate-tuned transitions electronic phases distinguished their polarization within the isospin space defined combination spin and momentum-space valley degrees freedom. Although all these are metallic at...
Bernal bilayer graphene hosts even-denominator fractional quantum Hall states thought to be described by a Pfaffian wave function with non-Abelian quasiparticle excitations. Here, we report the quantitative determination of energy gaps in using both thermally activated transport and direct measurement chemical potential. We find activation gap 5.1 K at B=12 T for half filled N=1 Landau level, consistent density matrix renormalization group calculations state. However, measured thermodynamic...
Energy bandgap largely determines the optical and electronic properties of a semiconductor. Variable therefore makes versatile functionality possible in single material. In layered material black phosphorus, can be modulated by number layers; as result, few-layer phosphorus has discrete values that are relevant for opto-electronic applications spectral range from red, monolayer, to mid-infrared bulk limit. Here, we further demonstrate continuous modulation mechanical strain applied through...
We describe an experimental technique to measure the chemical potential μ in atomically thin layered materials with high sensitivity and static limit. apply a quality graphene monolayer map out evolution of carrier density throughout N=0 N=1 Landau levels at magnetic field. By integrating over filling factor ν, we obtain ground state energy per particle, which can be directly compared numerical calculations. In level, our data show exceptional agreement calculations whole level without...
The advent of black phosphorus field-effect transistors (FETs) has brought new possibilities in the study two-dimensional (2D) electron systems. In a FET, gate induces highly anisotropic 2D and hole gases. Although gas reached high carrier mobilities that led to observation integer quantum Hall effect, improvement sample quality (2DEG) however been only moderate; effect remained elusive. Here, we obtain 2DEG by defining region with prepatterned graphite local gate. screens impurity potential...
Low-cost direct modulation detection (DM-DD) systems in optical communications are severely limited by transient chirps when adopting higher-order formats to meet the high-capacity transmission. To break through this constraint, a shaping current waveform technique combined with multi-level pulse amplitude (PAM) is proposed suppress chirp of directly modulated distributed feedback (DFB) lasers. This pre-compensation only requires simply changing injected waveform, which combination phase...
Recent terahertz-pump second-harmonic-generation(SHG)-probe measurements of quantum paraelectrics observed a significant long-lived non-oscillatory SHG component following an ultrafast resonant excitation the soft mode, which was interpreted as signature terahertz-induced transient ferroelectric order. Here we propose temperature-dependent dynamic model incorporating hot-phonon effect to simulate soft-mode behaviors under terahertz excitation. Its application paraelectric KTaO3 produces...
Recent terahertz-pump second-harmonic-generation(SHG)-probe measurements of quantum paraelectrics observed a significant long-lived non-oscillatory SHG component following an ultrafast resonant excitation the soft mode, which was interpreted as signature terahertz-induced transient ferroelectric order. Here we propose temperature-dependent dynamic model incorporating hot-phonon effect to simulate soft-mode behaviors under terahertz excitation. Its application paraelectric KTaO3 produces...
High mobility electron gases confined at material interfaces have been a venue for major discoveries in condensed matter physics. Ultra-high vacuum (UHV) technologies played key role creating such high-quality interfaces. The advent of two-dimensional (2D) materials brought new opportunities to explore exotic physics flat lands. UHV may once again revolutionize research low dimensions by facilitating the construction ultra-clean with wide variety 2D materials. Here, we describe design and...
We report quantum oscillation studies on the $\mathrm{B}{\mathrm{i}}_{2}\mathrm{T}{\mathrm{e}}_{3\ensuremath{-}x}{\mathrm{S}}_{x}$ topological insulator single crystals in pulsed magnetic fields up to 91 T. For $x=0.4$ sample with lowest bulk carrier density, surface and oscillations can be disentangled by combined Shubnikov--de Haas de Hass--van Alphen oscillations, as well nanometer-thick peeled crystals. At high beyond limit, our results suggest that zeroth Landau level of states is...
The phase diagram of an interacting two-dimensional electron system in a high magnetic field is enriched by the varying form effective Coulomb interaction, which depends strongly on Landau level index. While fractional quantum Hall states that dominate lower-energy levels have been explored experimentally variety systems, much less work has done to explore solids owing their subtle transport signatures and extreme sensitivity disorder. Here, we use chemical potential measurements map solid...
Sum frequency generation imaging microscopy was applied to visualize the internal electric-field behavior in operating organic field effect transistors.
1. Isospin magnetism and spin-triplet superconductivity in Bernal bilayer graphene Authors: Haoxin Zhou, Yu Saito, Liam Cohen, William Huynh, Caitlin L. Patterson, Fangyuan Yang, Takashi Taniguchi, Kenji Watanabe, Andrea F. Young arXiv:2110.11317 2. Superconductivity rhombohedral trilayer Tian Xie, Nature 598, 434–438 […]
Membranes of various phospholipids may separate into different domains at micrometer length scales the air-water interface. A significant challenge is to visualize molecular organization and obtain chemical information on this surface. Langmuir-Blodgett monolayers 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC) fused silica were investigated with compressive sensing sum frequency generation (SFG) microscopy. Before after mixing, SFG spectra...