We study devices made from individual nanotubes, nanowires and 2D layers like graphene, using electrical transport, low temperatures, high magnetic fields various optics, scanning probes, and other microscopies. The aim is to investigate new physics on the nanoscale such as the Luttinger liquid, the Fermi-edge singularity, conductance quantization, quantum Hall, the Kondo effect, charge pumping, metal-insulator transitions, phase transitions of adsorbates, photocurrent in graphene and nanowires, and ultrafast dynamics in topologically nontrivial and strongly correlated systems.
|Associate Professor (joint in EE)|
My group focuses on spin-systems in solids for quantum information processing (QIP) and sensing applications. Techniques including pump-probe, optical spin-echo, and high-resolution spectroscopy are used to further understand spin dynamics. Coupled optical-spin systems are integrated into nanophotonic devices to enable optical communications between spins for QIP and to increase magnetic sensitivity in sensing applications. Systems currently studied include semiconductor impurities, semiconductor quantum dots, and color centers in diamond.
My group focuses on growth and characterization of semiconductor nano-structures that combine a silicon substrate with nanoscale layers of materials with properties complementary to silicon, such as magnetism or light emission. Her research makes uses molecular beam epitaxy with in situ scanning probe microscopy and photoelectron spectroscopy, supplemented by ex situ structural, magnetic, optical and electrical measurements. She collaborates with Prof. Ohuchi (UW MSE) chalcogenide semiconductors with applications in nonvolatile memory.
My research focuses on the development and application of novel X-ray spectroscopies to problems of basic, industrial, and environmental interest. His group has constructed and commissioned the Lower Energy Resolution Inelastic X-ray scattering (LERIX) spectrometer at the Advanced Photon Source X-ray synchrotron at ANL. Our research emphasizes investigation of nano- and bulk-phase systems relevant for clean energy and basic questions involving correlated electron phenomenon in f-electron systems. We work closely with John Rehr's theory group.
|Associate Professor (joint in MSE)|
My group investigates new physics arising in solid state nanostructures. Our research involves nanomaterial synthesis, device fabrication, optical spectroscopy, and transport measurements. Currently we work on: high quality graphene growth; electronic, thermal, and optoelectronic properties of graphene and its integration of other nanophotonic systems; nonlinear optical spectroscopy of bilayer graphene with a tunable electronic bandgap; optical probing of topological insulators, ultrafast spectroscopy; and scanning photocurrent microscopy.
My primary research goals are directed towards discovery and understanding of novel collective behaviors in quantum materials. Particular examples include unconventional superconductivity emerging near a quantum critical point, and exotic Weyl/Dirac excitations in semimetals with strong spin-orbit coupling. We focus on crystal growth, thermodynamic and magnetic measurements, and novel experimental techniques that utilize strain to probe and manipulate the symmetry properties of materials.
|Assistant Professor (joint in MSE)|
|Nano- and Quantum Photonics|
My group focuses on novel nanophotonic devices based on principle cavity quantum electrodynamics. Our research involves using concepts of fundamental physics to build devices with applications in optical computing, communication and sensing. To that end, we are studying new materials including two-dimensional materials, phase-change materials and complex oxides, which will be integrated on photonic devices made of silicon, silicon nitride and gallium phosphide. Along with novel materials, we also study emerging nanophotonic devices based on photonic crystal and dielectric metasurface.
|Low temperature Physics|
We study the thermodynamic, structural and dynamic properties of a single or a few atomic/molecular layer films adsorbed (deposited) on interesting surfaces. This topic is related to the behavior of matter in one- and two-dimensions (1d and 2d), the crossover from 1d to 2d, and how bulk (3d) matter grows (or doesn't grow) on selected surfaces. The research is done at temperatures between 1.5K and 300 K.