Past Events

  • Special Condensed Matter Seminar: "Shining light on topological insulators and Weyl semimetals"

    David Rittenhouse Laboratory, A4

    Liang Wu, University of California, Berkeley

    The last decade has witnessed an explosion of research investigating the role of topology in band-structure, as exemplified by the wealth of recent works on topological insulators (TIs) and Weyl semimetals (WSMs). In this talk I hope to convince you that optical probes of solids give unique insight into these topological states of matter.

  • Special Condensed Matter Seminar: "Probing Topological Valley Physics in Bilayer Graphene"

    David Rittenhouse Laboratory, A4

    Long Ju, Cornell University

    Graphene has been a model solid state system where novel quantum phenomena emerge from the interplay between symmetry, band topology and reduced dimensionality. In particular, AB-stacked bilayer graphene has a unique bandstructure with an electrically tunable bandgap and a valley-dependent Berry phase. These features result in unusual electrical and optical properties, for which optical spectroscopy/microscopy are powerful characterization tools.

  • Astro Seminar: "Quenching and Bulge Growth Over Cosmic Time in Massive Galaxies"

    David Rittenhouse Laboratory, A4

    Marc Huertas-Company (Paris Observatory)

    The life of a galaxy is a balance between processes that trigger star formation by accelerating gas cooling and others which tend to prevent stars to form by expelling or heating gas.  Over the past years, the picture is emerging that, during most of its life, a galaxy seems to live a rather quiet life, gradually growing in stellar mass through the formation of new stars which are formed at a rate remarkably proportional to its stellar mass, This is interpreted as an indirect evidence that fuel in the form of cold gas is somehow continuously being fed into the galaxies to susta

  • Math-Bio seminar: "Fast, scalable prediction of deleterious noncoding variants from genomic data"

    318 Carolyn Lynch Laboratory

    Adam Siepel, Cold Spring Harbor Laboratory

    Across many species, a large fraction of genetic variants that influence phenotypes of interest is located outside of protein-coding genes, yet existing methods for identifying such variants have poor predictive power. Here, we introduce a new computational method, called LINSIGHT, that substantially improves the prediction of noncoding nucleotide sites at which mutations are likely to have deleterious fitness consequences, and which therefore are likely to be phenotypically important.

  • Special Condensed Matter Seminar: "Non-equilibrium dynamics of a frustrated Mott insulator"

    David Rittenhouse Laboratory, A4

    Zhanybek Alpichshev, M.I.T.

    What happens to electrons when both the spin orbit coupling and inter-particle Coulomb repulsion are very strong? While SOC alone can change the topology of the single particle insulating state, even short range on-site repulsion by itself can give rise to a Mott insulator - one of the most mysterious and thought provoking phases in solid state physics. In this seminar I will talk about the behaviour of quasiparticles in a frustrated Mott insulator in the presence of strong spin-orbit coupling.
  • ADVANCES IN BIOMEDICAL OPTICS: Exploring Brain Interactions with Diffuse Optics

    B1 Stellar Chance Laboratories, 440 Curie Blvd

    Rickson Mesquita (University of Campinas)

    The human brain can be seen as a complex system due to its functional capabilities and structural organization. Indeed, previous works employing functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) have shown several complex features of the brain.  In this talk I will approach how one can employ diffuse optics to reveal the brain's complex features during the resting state. In particular, I will discuss our recent results on the use of graph theory to characterize the spatial interactions of the healthy and the diseased brain. Last, I will explore potential clinical applications of our methodology, mostly on brain development and rehabilitation

    (Pizza will be served at 11:45 am)

  • Department Colloquium: "The Pope of Physics: Enrico Fermi and the Birth of the Atomic Age"

    David Rittenhouse Laboratory, A8

    Gino Segre (University of Pennsylvania) and Bettina Hoerlin

    Enrico Fermi was unique in a number of ways, including the staggering breadth of his research, from relativity theory and magnetohydrodynamics to instrument development. He was the only 20th century physicist to have attained the very heights of the profession as a theorist and experimentalist as well as the only one to be essentially self-taught. His 1938 Nobel Prize was picked up en route in his flight from fascist Italy with his Jewish wife and children to find a new life in America.

  • Department of Physics and Astronomy: Postponed Exams

    DRL, A1

    Fall 2016 Postponed Exam

    ALL EXAMS ARE FROM 6:00 PM TO 8:00 PM UNLESS NOTED OTHERWISE.

  • Astro Seminar: "Cosmology Large Angular Scale Surveyor (CLASS)"

    David Rittenhouse Laboratory, 4C8

    Zhilei Xu (Johns Hopkins University)

    Cosmology Large Angular Scale Surveyor (CLASS) is an array of telescopes to observe Cosmic Microwave Background (CMB) in Chile. CLASS will make large angular scale CMB polarization measurements in frequency bands at 40 GHz, 90 GHz, 150 GHz and 220 GHz. The five-year CLASS survey will constrain the tensor-to-scalar ratio at the 0.01 level, and also provide more information on reionization, the sum of neutrino mass and the Galactic interstellar medium. In my talk, I will introduce the science and design of CLASS experiment.

  • Special Condensed Matter Seminar: "Real-space imaging of a nematic quantum liquid"

    David Rittenhouse Laboratory, A4

    Ben Feldman, Princeton University

    Electronic phases in condensed matter systems generally respect the symmetries of their solid state host. However, interactions among electrons can give rise to a variety of exotic correlated states characterized by broken symmetry. An intriguing example is the formation of electron fluids with wave functions that spontaneously break the symmetry of the underlying lattice. These phases are quantum analogues of classical liquid crystals and have recently attracted interest across disparate platforms ranging from high-temperature superconductors to two-dimensional electron systems.