Colloquia & Seminars
  • Physics Colloquium
    Speaker Name: Matthias Troyer

    Speaker Institution: ETH Zürich

    Title: Validation of quantum devices: from quantum random numbers to the D-Wave devices

    Abstract: About a century after the development of quantum mechanics we have now reached an exciting time where non-trivial devices that make use of quantum effects can be built. While a universal quantum computer of non-trivial size is still out of reach there are a number commercial and experimental devices: quantum random number generators, quantum encryption systems, and analog quantum simulators. In this colloquium I will present some of these devices and validation tests we performed on them. Quantum random number generators use the inherent randomness in quantum measurements to produce true random numbers, unlike classical pseudorandom number generators which are inherently deterministic. Optical lattice emulators use ultracold atomic gases in optical lattices to mimic typical models of condensed matter physics. Finally, I will discuss the devices built by Canadian company D-Wave systems, which are special purpose quantum simulators for solving hard classical optimization problems.
    When: Tue, September 2, 2014 - 4:00pm
    Where: Lobby of the Physical Sciences Complex
  • Applied Dynamics Seminars
    Speaker Name: Yue-Kin Tsang

    Speaker Institution: University of Edinburgh

    Title: "Advection-condensation of water vapor in a model of coherent stiring" and "An energy-enstrophy method for nonlinear stability in two-dimensional hydrodynamics"
    When: Thu, September 4, 2014 - 12:30pm
    Where: IREAP Large Conference Room, ERF 1207
  • Refreshments for CNAM Cond. Matter Colloquium

    When: Thu, September 4, 2014 - 1:30pm
    Where: Phys room 1305F, the "new" Toll Room
  • CNAM Condensed Matter Colloquium
    Speaker: Dr. Kyle Shen, Cornell University

    Title: Controlling and Observing Electronic Structure in Artificial Quantum Materials

    Abstract: Our ability to control the electronic properties of materials, for instance at semiconductor interfaces, has had enormous scientific and technological implications. Recently, this concept has been extended to materials which possess inherently strong quantum many-body interactions, such as strongly correlated transition metal oxides. Epitaxial thin films offer a number of unique advantages for manipulating the electronic properties of correlated transition metal oxides. For example, atomically thin films or abrupt interfaces can be synthesized to artificially confine electrons in two dimensions. Furthermore, using a substrate with a mismatched lattice constant can impose large biaxial strains of larger than 3% ($\Delta a / a), much larger than can achieved in bulk single crystals. Since these dimensionally confined or strained systems may necessarily be less than a few unit cells thick, investigating their properties can be particularly challenging. We employ a combination of reactive oxide molecular beam epitaxy (MBE) and angle-resolved photoemission spectroscopy (ARPES) to investigate how dimensional confinement and epitaxial strain can be used to manipulate electronic properties and structure in correlated transition metal oxide thin films. In particular, we report on a number of model systems : a thickness-driven metal-insulator transition in ultrathin LaNiO3 epitaxial thin films, and a strain-driven Lifshitz transition in the spin-triplet ruthenate superconductor Sr2RuO4.

    Host: James Williams
    When: Thu, September 4, 2014 - 2:00pm
    Where: Phys room 1201
  • Organizational Meeting (RIT on Geometry and Physics)
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    When: Thu, September 4, 2014 - 3:30pm
    Where: PHY 1117
  • MCFP Seminar
    Speaker Name: Peter Graham

    Speaker Institution: Stanford University

    Title: Cosmological Production and Detection of Hidden Sectors

    Abstract: tk
    When: Thu, September 4, 2014 - 4:00pm
    Where: PSC 3150
  • JQI Special Seminar
    Speaker Name: Peter Graham

    Speaker Institution: Stanford University

    Title: Gravitational Wave Detection with Atom Interferometry

    Abstract: Atom interferometry is an exciting tool for testing gravity and searching for gravitational waves. A new detection strategy based on advances in optical atomic clocks and atom interferometry can operate at long-baselines and provides immunity to laser frequency noise. This new class of sensor allows sensitive gravitational wave detection with only a single baseline. I will describe our proposals for gravitational wave detection and tests of gravity with atom interferometry, and discuss recent experimental progress.
    When: Fri, September 5, 2014 - 3:00pm
    Where: CSS 2115
  • JQI Seminar
    Speaker Name: Howard Carmichael

    Speaker Institution: University of Auckland, New Zealand

    Title and Abstract to follow

    Host: Luis Orozco
    When: Mon, September 8, 2014 - 11:00am
    Where: CSS 2400
  • EPT Seminar
    Title: tk

    Speaker: Gustavo Tavares, Boston University

    Abstract: tk
    When: Mon, September 8, 2014 - 3:00pm
    Where: PSC 3150
  • CMTC Seminar
    Speaker: Andrea Young (Pappalardo Fellow, MIT)

    Title: Tuning and probing symmetry breaking in graphene quantum Hall ferromagnets

    Abstract:

    In monolayer and bilayer graphene, the carbon sublattices endow the electron wavefunctions with an additional valley degeneracy. At high magnetic fields, this manifests as highly symmetric multicomponent Landau levels, in which the dominant mechanism for symmetry breaking is due to electronic interactions. In this talk, I will discuss our recent efforts to probe and manipulate the resulting many body ground states. First I will describe experiments on charge neutral monolayer graphene, in which the nature of the symmetry breaking within the combined spin/valley space is directly linked to the edge state structure. Using large in-plane magnetic fields, we induce a quantum spin Hall (QSH) effect analogous to time reversal symmetry protected topological insulators but protected by an emergent spin-rotation symmetry. The properties of the resulting helical edge states can be modulated by balancing the applied field against an intrinsic antiferromagnetic instability, which tends to spontaneously break the spin-rotation symmetry. In the resulting canted antiferromagnetic (CAF) state, we observe transport signatures of gapped edge states, which constitute a new kind of one-dimensional electronic system with tunable band gap and associated spin-texture.

    Finally I will discuss recent experiments in bilayer graphene, where the sublattices giving rise to the valley degeneracy are on different layers. We use this fact to capacitively detect the layer polarization in bilayer graphene, allowing us to directly constrain the order parameter across a wide range of parameters.

    Host: Jay Sau

    http://www.physics.umd.edu/cmtc/seminars.html
    When: Tue, September 9, 2014 - 11:00am
    Where: 2205 Physics Building
  • Physics Colloquium
    Speaker Name: Jaeyoung Park

    Speaker Institution: E=mc2

    Title: Measurement of Enhanced Confinement at High Pressure Magnetic Cusp System

    Abstract: 56 years ago, Harold Grad and his team at New Your University conjectured (and to some extent calculated) that the confinement properties of a magnetic cusp would be dramatically improved if the confined plasma had sufficiently high pressure to exclude the B-field from the interior. We have carried out an experiment that demonstrates, for the first time, that this effect is real. This has dramatic implications for the future of cusp confined fusion.
    When: Tue, September 9, 2014 - 4:00pm
    Where: Lobby of the Physical Sciences Complex
  • Refreshments for CNAM Cond. Matter Colloquium

    When: Thu, September 11, 2014 - 1:30pm
    Where: Phys. room 1305F, the "new" Toll Room
  • CNAM Condensed Matter Colloquium
    Speaker: Dr. Tyrel McQueen, Johns Hopkins
    Title & Abstract: TBD
    When: Thu, September 11, 2014 - 2:00pm
    Where: Phys room 1201
  • JQI Special Seminar
    Speaker Name: Michal Lipson

    Speaker Institution: Cornell

    Title and Abstract to follow
    Host: Luis Orozco
    When: Mon, September 15, 2014 - 11:00am
    Where: CSS 2400
  • Physics Colloquium
    Speaker Name: Mark Dykman

    Speaker Institution: Michigan State University (East Lansing)

    Title: Nonlinear oscillators: quantum activation, quantum measurements, quantum heating

    Abstract:
    When: Tue, September 16, 2014 - 4:00pm
    Where: PSC Lobby
  • Refreshments for the CNAM Condensed Matter Colloquium

    When: Thu, September 18, 2014 - 1:30pm
    Where: Room 1305F, the "new" Toll Room
  • CNAM Cond. Matter Colloquium
    Speaker Name: Dr. Leonid Rokhinson

    Speaker Institution: Purdue

    Title & Abstract: TBD
    When: Thu, September 18, 2014 - 2:00pm
    Where: Phys room 1201
  • JQI Seminar
    Speaker Name: Brian DeMarco

    Speaker Institution: University of Illinois

    Host: James Williams

    Title and Abstract to follow
    When: Mon, September 22, 2014 - 11:00am
    Where: CSS 2400
  • EPT Seminar
    Title: tk

    Speaker: Gilly Elor, MIT

    Abstract: tk
    When: Mon, September 22, 2014 - 3:00pm
    Where: PSC 3150
  • Physics Colloquium
    Speaker Name: Brian DeMarco

    Speaker Institution: University of Illinois at Urbana

    Title: Ultracold Disordered Quantum Gases

    Abstract: Disorder is the rule, rather than the exception, in nature. Despite this, we understand little about how disorder affects interacting quantum matter. I will give an overview of our experiments using ultracold atom gases to probe paradigms of interacting disordered quantum particles. We introduce disorder to naturally clean atomic gases cooled to billionths of a degree above absolute zero using focused optical speckle. I will explain how we observe Anderson localization---a spectacular phenomenon in which interference prevents waves from propagating in a disordered medium---of quantum matter in three dimensions. I will also show how we combine speckle with an optical crystal to emulate a completely tunable and precisely characterized disordered quantum solid. In these optical lattice experiments, we realize disordered Hubbard models that we use to answer critical questions regarding how disorder impacts the properties of electronic solids, such as superconductors and metals.
    When: Tue, September 23, 2014 - 4:00pm
    Where: PSC Lobby
 

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