A5018329199- Spectroscopy and Quantum Chemical Studies
- Advanced Chemical Physics Studies
- Atomic and Subatomic Physics Research
- Physics of Superconductivity and Magnetism
- Electron Spin Resonance Studies
- Magnetic and transport properties of perovskites and related materials
- Chromatin Remodeling and Cancer
- Electronic and Structural Properties of Oxides
- Magnetic properties of thin films
- Advanced Condensed Matter Physics
- Advanced Physical and Chemical Molecular Interactions
- Iron-based superconductors research
- Mechanical and Optical Resonators
- Amyloidosis: Diagnosis, Treatment, Outcomes
- Laser-Matter Interactions and Applications
- Mass Spectrometry Techniques and Applications
- Topological Materials and Phenomena
- Quantum, superfluid, helium dynamics
- Surface Roughness and Optical Measurements
- Rare-earth and actinide compounds
- Neural Networks and Applications
- Computational Physics and Python Applications
- Advanced Materials Characterization Techniques
- Advanced Electron Microscopy Techniques and Applications
- Electrochemical Analysis and Applications
University of British Columbia
2019-2022
Max Planck Institute for Chemical Physics of Solids
2019
Ultrafast spectroscopies have become an important tool for elucidating the microscopic description and dynamical properties of quantum materials. In particular, by tracking dynamics non-thermal electrons, a material's dominant scattering processes -- thus many-body interactions between electrons collective excitations can be revealed. Here we present new method extracting electron-phonon coupling strength in time domain, means angle-resolved photoemission spectroscopy (TR-ARPES). This is...
With its direct correspondence to electronic structure, angle-resolved photoemission spectroscopy (ARPES) is a ubiquitous tool for the study of solids. When extended temporal domain, time-resolved (TR)-ARPES offers potential move beyond equilibrium properties, exploring both unoccupied structure as well dynamical response under ultrafast perturbation. Historically, extreme ultraviolet sources employing high-order harmonic generation (HHG) have required compromises that make it challenging...
Superconductivity and charge density waves (CDWs) are competitive, yet coexisting, orders in cuprate superconductors. To understand their microscopic interdependence, a probe capable of discerning interaction on its natural length time scale is necessary. We use ultrafast resonant soft x-ray scattering to track the transient evolution CDW correlations YBa2Cu3O6+x after quench superconductivity by an infrared laser pulse. observe nonthermal response order characterized near doubling...
In spintronics, the two main approaches to actively control electrons' spin involve static magnetic or electric fields. An alternative avenue relies on use of optical fields generate currents, which can bolster spin-device performance, allowing for faster and more efficient logic. To date, research has mainly focused injection currents through photogalvanic effect, little is known about direct intrinsic spin-splitting. explore manipulation a material's properties, we consider Rashba effect....
Abstract Fundamental research on two-dimensional (2D) magnetic systems based van der Waals materials has been gaining traction rapidly since their recent discovery. With the increase of knowledge, it become clear that such have also a strong potential for applications in devices combine magnetism with electronics, optics, and nanomechanics. Nonetheless, many challenges still lay ahead. Several fundamental aspects 2D are unknown or poorly understood, as often-complicated electronic structure,...
Time- and angle-resolved photoemission spectroscopy (TR-ARPES) accesses the electronic structure of solids under optical excitation, is a powerful technique for studying coupling between electrons collective modes. One approach to infer electron-boson through relaxation dynamics optically-excited electrons, characteristic timescales energy redistribution. A common description electron effective temperature. Such requires that thermodynamic quantities are well-defined, an assumption generally...
Amongst the iron-based superconductors, LiFeAs is unrivalled in simplicity of its crystal structure and phase diagram. However, our understanding this canonical compound suffers from conflict between mutually incompatible descriptions material's electronic structure, as derived contradictory interpretations photoemission record. Here, we explore challenge interpretation such experiments. By combining comprehensive photon energy- polarization- dependent angle-resolved spectroscopy (ARPES)...
We present a method for producing high quality $\mathrm{K}{\mathrm{Co}}_{2}{\mathrm{As}}_{2}$ crystals, stable in air and suitable variety of measurements. X-ray diffraction, magnetic susceptibility, electrical transport, heat capacity measurements confirm the an absence long range order down to at least 2 K. Residual resistivity values approaching 0.25 $\ensuremath{\mu}\mathrm{\ensuremath{\Omega}}$ cm are representative low impurity scattering, Sommerfeld coefficient...
Fundamental research on two-dimensional (2D) magnetic systems based van der Waals materials has been gaining traction rapidly since their recent discovery. With the increase of knowledge, it become clear that such have also a strong potential for applications in devices combine magnetism with electronics, optics, and nanomechanics. Nonetheless, many challenges still lay ahead. Several fundamental aspects 2D are unknown or poorly understood, as often-complicated electronic structure, optical...
High-temperature superconducting cuprates exhibit an intriguing phenomenology for the low-energy elementary excitations. In particular, unconventional temperature dependence of coherent spectral weight (CSW) has been observed in phase by angle-resolved photoemission spectroscopy (ARPES), both at antinode where d-wave paring gap is maximum, as well along gapless nodal direction. Here, we combine equilibrium and time-resolved ARPES to track dependent meltdown CSW Bi-based with unprecedented...
Controlling magnetic textures at ever smaller length and time scales is of key fundamental technological interest. Achieving nanoscale control often relies on finding an external stimulus that able to act small scales, which highly challenging. A promising alternative achieve using the inhomogeneity texture itself. Using a multilayered ferromagnetic Pt/Co/Pt thin-film structure as model system, we employ force microscope investigate change in nanotextures induced by circularly polarized...
The 40-70 meV band-structure renormalization (so-called kink) in high-temperature cuprate superconductors - which has been mainly interpreted terms of electron-boson coupling is observed to be strongly suppressed both above the superconducting transition temperature and under optical excitation. We employ equilibrium time- angle-resolved photoemission spectroscopy, combination with Migdal-Eliashberg simulations, investigate suppression near-nodal kink Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$. show...