Femtosecond Coherent Multidimensional Vibronic Spectroscopy Multidimensional coherent spectroscopy such as two-dimensional infrared and two-dimensional electronic spectroscopy have become important tools to monitor complex non-equilibrium quantum phenomena. Recently we have developed multicolor spectroscopy combining a train of infrared and optical pulses to probe coupled vibrational and electronic coordinates ...more
Shedding New Light on Photosynthetic Systems Using Multidimensional Spectroscopies The primary events of photosynthesis occur on ultrafast timescales with high quantum efficiency. Elucidating the design principles of photosynthetic systems remains an outstanding challenge that has the potential to impact our design of artificial light-harvesting materials ...more
Spin, Charge, and Phonon Coupling Effects in 2D Materials The coupling between spin, charge, and lattice degrees of freedom plays an important role in a wide range of fundamental phenomena. 2D material is an emerging platform for studying these coupling effects. In this talk, I will present a couple examples along this direction ...more
Controlling Coherent Light-Matter Interactions in Semiconductors Coherent light-matter interactions provide a powerful means to study and control interacting matter excitations. Using the mature, III-Arsenide semiconductor system, we incoporate a designable photonic crystal mirror to control hybrid light-matter coupled modes (polaritons) ...more
Connecting and scaling semiconductor quantum systems At the core of most quantum technologies, including quantum networks, quantum computers and quantum simulators, is the development of homogeneous, long lived qubits with excellent optical interfaces, and the development of high efficiency and robust optical interconnects for such qubits ...more
Moiré superlattices: a new Hubbard model simulator? The Hubbard model, first formulated by physicist John Hubbard in the 1960s, is a simple theoretical model of interacting quantum particles in a lattice. The model is thought to capture the essential physics of high-temperature superconductors, magnetic insulators, and other complex emergent quantum many-body ground states ...more
Controlling Correlations: Linear-, Nonlinear-, and Hydrodynamics in Quantum Matter The physics of quantum matter is rich with excited-state and nonequilibrium effects, but many of these phenomena remain poorly understood and, consequently, technologically unexplored. My group’s research, therefore, focuses on how quantum systems behave, particularly away from equilibrium, and how we can harness these effects ...more
Stanford University, USA To thermalize or not to thermalize? We will discuss two experiments designed to investigate how integrable quantum many-body systems do or do not thermalize in the presence of integrability breaking perturbations. In the first experiment, a quantum Newton's cradle is set in motion under different strengths of a magnetic interaction among the dysprosium atoms in an ultracold 1D gas ... more
Duke University, USA Extreme Photonics with Nanogap Cavities Nano- and quantum materials with unique optical properties hold the potential for breakthroughs in a wide range of areas from ultrafast optoelectronics and on-chip components for quantum information science to improved bio-sensing. An exciting opportunity to realize such new materials lies in controlling the local electromagnetic environment on the atomic- and molecular-scale (~1-10 nm), which enables extreme local field enhancements and drastically modified local density of states ... more
ICFO - The Institute of Photonic Sciences, Barcelona, Spain
Polaritons and ultrasmall cavities in twisted 2D material heterostructures Two-dimensional (2D) materials offer extraordinary potential for control of light and light-matter interactions at the atomic scale. Twisted 2D materials has recently attracted a lot of interest, due to the capability to induce moiré superlattices and discovery of electronic correlated phases. In this talk, we present nanoscale optical techniques such as near-field optical microscopy, and reveal with nanometer spatial resolution unique observations of topological domain wall boundaries and interband collective modes in charge neutral twisted-bilayer graphene near the magic angle ... more
