The nature and structure of matter and energy remains one of mankind’s leading research frontiers. The faculty members involved in this area are engaged in experimental and theoretical studies of the fundamental interactions of matter at sub-femtometer distances. Another research focus is on the direct detection of dark matter with the XENON100 and XENON1T experiments operated in the LNGS laboratory in Italy. Research & development efforts for these and future dark matter experiments addresses xenon purification techniques to operate the most radiopure detectors in the world.
Experimental research in the astrophysics group focuses on near-field cosmology, in which local galaxies are studied as examples to understand the properties of the Universe, including dark matter and dark energy. We particularly focus on the dynamics and structure of the Milky Way as revealed by large, international photometric and spectroscopic surveys such as the Sloan Digital Sky Survey (SDSS) and the Large Area Multi-Object Spectroscopic Telescope (LAMOST), and by astrometric surveys such as Gaia. Dwarf galaxies are ripped apart by tidal forces in the Milky Way into tidal streams.
The experimental condensed matter research distinguishes between the bulk of matter, its surface and interface, and proceeds in close partnership with theory and computational studies. Of interest are new concepts, materials, and techniques for nanotechnology and green technology such as renewable energy, energy conservation and conversion, storage, and delivery. Some projects are interdisciplinary and take part in dedicated Centers across the Institute.
Plasmons, quasiparticles arising from the collective motion of electrons on the surface of a metal, can strongly modify the behavior of nearby light, and could be instrumental in building some of the key components of a quantum circuit.
One of the major developments of the last two decades has been the ever-increasing interconnectivity of a broad class of information networks, including physical and data network types arising in telecommunication, social networks, and transportation and energy infrastructures. This interconnectivity has led to immense temporal and spatial complexity in modern networks and a critical need for basic mathematical theory and statistical modeling of complex interacting networks.
Activities in this area primarily focus on investigations on beyond the standard model applications of lattice field theory. This includes strongly coupled supersymmetric systems such as arise in hidden sector models of spontaneous supersymmetry breaking. We have also studied models of compositeness in the Higgs sector of the Standard Model, with electroweak symmetry broken by strong dynamics of a new gauge force. This has led us into developing software for the study of resonance properties from first principles, which is also useful for lattice quantum chromodynamics.
Research in optical physics covers a wide range of activities related to photons and their interaction with various materials. Experimental and theoretical research is ongoing to provide innovative solutions to today’s problems in both fundamental and application. The goals are the development of novel nanoelectronic and nanophotonic devices, creative solutions for homeland security, renewable energies, biological and biomedical investigations, solar harvesting, and smart lighting.
Theoretical and computational studies performed include the electronic structure of nanostructured material, models for the structure and electronic properties of surfaces and interfaces and the binding and mobility of adsorbed atoms on metal surfaces, molecular electronics and spintronics, as well as developing understanding of far-from-equilibrium physics.
Current research focuses on determining the location of dark matter in the Milky Way. We perform n-body simulations of the tidal disruption of dwarf galaxies in the Milky Way halo, using MilkyWay@home, a 0.5 PetaFLOPS volunteer computing platform built in-house. We compare the simulations to actual Milky Way data to determine the best parameters for the simulations, thus constraining the amount and distribution of dark matter in the halo.