A5076783570- 2D Materials and Applications
- Topological Materials and Phenomena
- Physics of Superconductivity and Magnetism
- Quantum and electron transport phenomena
- Advanced Condensed Matter Physics
- Magnetic properties of thin films
- Magnetic and transport properties of perovskites and related materials
- Graphene research and applications
- Mechanical and Optical Resonators
- Electronic and Structural Properties of Oxides
- Iron-based superconductors research
- Acoustic Wave Resonator Technologies
- Magnetic Field Sensors Techniques
- Molecular Junctions and Nanostructures
- ZnO doping and properties
- Rare-earth and actinide compounds
- Ferroelectric and Negative Capacitance Devices
- Complex Systems and Time Series Analysis
- Terahertz technology and applications
- Multiferroics and related materials
- Atomic and Subatomic Physics Research
- Nanowire Synthesis and Applications
University of Washington
2019-2024
University of Toronto
2020
Ionic substitution forms an essential pathway to manipulate the carrier density and crystalline symmetry of materials via ion-lattice-electron coupling, leading a rich spectrum electronic states in strongly correlated systems. Using ferromagnetic metal SrRuO3 as model system, we demonstrate efficient reversible control both through ionic liquid gating induced protonation. The insertion protons electron-dopes SrRuO3, exotic paramagnetic phase transition along with increase proton...
Direct optical probing of the antiferromagnetic order parameter in atomically thin samples is challenging, for example, via magneto-optical spectroscopy, due to lack net magnetization. Here, we report zigzag-antiferromagnetism (AFM) induced linear dichroism (LD) layered transition-metal thiophosphate FePS3 down monolayer limit. The observed LD giant despite having wave vector parallel Néel vector. at least one magnitude larger than those reported other systems, where orthogonal large enables...
van der Waals (vdW) magnets have emerged as a tunable platform for exploring variety of layer-dependent magnetic phenomena. Here we probe the thickness-dependent magnetism vanadium triiodide (VI3), material known layered ferromagnetic Mott insulator in its bulk form, using circular dichroism microscopy. Robust ferromagnetism is observed all thin layers, down to monolayer limit with large coercive fields. In contrast vdW magnets, Curie temperature shows an anomalous increase layer number...
The interplay between a multitude of electronic, spin, and lattice degrees freedom underlies the complex phase diagrams quantum materials. Layer stacking in van der Waals (vdW) heterostructures is responsible for exotic electronic magnetic properties, which inspires control two-dimensional magnetism. Beyond order interlayer magnetism, we discover spin-shear coupling mechanism subtle shear atomic layers can have profound effect on intralayer family vdW antiferromagnets. Using time-resolved...
Uniaxial strain has been widely used as a powerful tool for investigating and controlling the properties of quantum materials. However, existing techniques have so far mostly limited to use with bulk crystals. Although recent progress made in extending application two-dimensional van der Waals (vdW) heterostructures, these optical characterization extremely simple electrical device geometries. Here, we report piezoelectric-based \textit{in situ} uniaxial technique enabling simultaneous...
Strong spin-lattice coupling in van der Waals (vdW) magnets shows potential for innovative magneto-mechanical applications. Here, nanoscale and picosecond imaging by ultrafast electron microscopy reveal heterogeneous spin-mediated coherent acoustic phonon dynamics a thin-film cavity of the vdW antiferromagnet FePS3. The harmonics interlayer shear modes are observed, which even odd exhibit distinct nanoscopic dynamics. Corroborated wave simulation, role defects forming is elucidated. Above...
We study the magneto-optical Kerr effect (MOKE) in SrRuO$_3$ thin films, uncovering wide regimes of wavelength, temperature, and magnetic field where rotation is not simply proportional to magnetization but instead displays two-component behavior. One component MOKE signal tracks average magnetization, while second "anomalous" bears a resemblance anomalies Hall resistivity which have been previously reported skyrmion materials. present theory showing that arise from non-monotonic relation...
Understanding surface collective dynamics in quantum materials is crucial for advancing technologies. For example, phonon modes paraelectrics are thought to be essential facilitating interfacial superconductivity. However, detecting these modes, especially below 1 terahertz, challenging because of limited sampling volumes and the need high spectroscopic resolution. Here, we report soft transverse optical (TO1) KTaO 3 SrTiO by surface-sensitive spintronic terahertz spectroscopy that can sense...
Emergent cooperative motions of individual degrees freedom, i.e. collective excitations, govern the low-energy response system ground states under external stimulations and play essential roles for understanding many-body phenomena in low-dimensional materials. The hybridization distinct modes provides a route towards coherent manipulation coupled freedom quantum phases. In magnets, strong coupling between spin lattice i.e., magnons phonons, can lead to quasi-particle magnon polarons. Here,...
Electronic nematicity, a state in which rotational symmetry is spontaneously broken, has become familiar characteristic of many strongly correlated materials. One widely studied example the discovered Ising-nematicity and its interplay with superconductivity tetragonal iron pnictides. Since nematic directors crystalline solids are restricted by underlying crystal symmetry, recently identified quantum material systems three-fold (C$_3$) offer new platform to investigate order three-state...
Uniaxial strain has been widely used as a powerful tool for investigating and controlling the properties of quantum materials. However, existing techniques have so far mostly limited to use with bulk crystals. Although recent progress made in extending application two-dimensional van der Waals (vdW) heterostructures, these optical characterization extremely simple electrical device geometries. Here, we report piezoelectric-based situ uniaxial technique enabling simultaneous transport...
Understanding surface collective dynamics in quantum materials is crucial for advancing technologies. For example, phonon modes paraelectrics are thought to play an essential role facilitating interfacial superconductivity. However, detecting these modes, especially below 1 terahertz (THz), challenging due limited sampling volumes and the need high spectroscopic resolution. Here, we report soft transverse optical (TO1) KTaO3 SrTiO3 by developing surface-sensitive spintronic THz spectroscopy...