Upcoming Events For Colloquia
Wed Mar 3, 2021
Physics Colloquium: Dr. Ilya K. Drozdov, Brookhaven National Laboratory
4:00 PM - 5:00 PM
zoom
Physics Colloquium
Synthesizing and visualizing Majorana modes
Dr. Ilya K. Drozdov
Assistant Scientist at the Condensed Matter Physics and Materials Science Division
Brookhaven National Laboratory
In this talk, I will give an introduction to topological phases of matter, topological superconductivity, and, more specifically, excitations of a topological superconductor known as Majorana modes. I will discuss experimental progress in realizing topological phases in materials and observing spectroscopic signatures of those phases with the focus on scanning tunneling microscopy (STM) experiments. One example of such behavior is found in elemental Bismuth, a material that attracted a lot of attention due
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Thu Mar 4, 2021
Physics Colloquium: Dr. Hryhoriy Polyshyn, UCSB
4:00 PM - 5:00 PM
zoom
Physics Colloquium
Orbital Chern insulators in flat-band graphene moiré systems
Dr. Hryhoriy Polshyn
Postdoctoral Scholar, Department of Physics
University of California Santa Barbara
Taming topological electronic phases is one of the central problems of modern condensed matter physics and a prerequisite for new technologies such as topological quantum computation. Realizing topological phases at zero magnetic field has been a longstanding goal since Haldane’s theoretical proposal of the quantum anomalous Hall (QAH) state. My talk will focus on newly discovered QAH states that emerge in twisted bilayer and trilayer graphene systems. In contrast to magnetically doped topological insulators, the QAH states in these moiré systems are driven by intrinsic strong interactions, which polarize the electrons into a single moiré miniband with Chern number of C = 1 or 2. Remarkably, the magnetization of these “orbital Chern insulators” (OCI) arises predominantly from the orbital motion of the electrons rather than the electron spin. I will discuss a novel effect originating from the curious magnetic properties of OCIs that enables non-volatile electrical switching of the magnetic and topological orders. Finally, I will present recent studies of the OCIs that emerge at half-fillings of moiré minibands and spontaneously break the moiré superlattice symmetry.…
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Fri Mar 5, 2021
Physics Colloquium: Dr. Xiaolong Liu, Cornell University
12:45 PM - 1:45 PM
zoom
Physics Colloquium
Visualizing Electron-Pair Fluids and Crystals at the Atomic Scale
Dr. Xiaolong Liu
Kavli Fellow, Physics
Cornell University
Pairing of electrons with opposite momenta takes place inside most conventional superconductors, leading to translationally invariant fluids of electron pairs. Meanwhile, electron pairs can form crystals known as pair density waves (PDWs) that break translational symmetry. Experimental evidence of PDWs, however, remains scarce due to the difficulty in imaging the superconducting condensate. In this talk, I will first introduce our recent discovery of a PDW state in a transition metal dichalcogenide, NbSe 2 , using atomic-resolution scanned Josephson-tunneling microscopy (SJTM). We observe two characteristic signatures of PDWs including periodic modulations of electron-pair density and superconducting energy gap at the wavevectors of preexisting charge density waves. Using the same SJTM technique, I will then discuss our capability in visualizing the velocity field and supercurrent density of electron-pair fluid flow around quantum vortices. Finally, I will share my perspective on applications of such novel techniques in other emerging quantum materials.…
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Wed Mar 10, 2021
Physics Colloquium: Dr. Na Hyun Jo, Lawrence Berkeley National Laboratory
4:00 PM - 5:00 PM
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Physics Colloquium
Synthesizing, Understanding, and Controlling Quantum Materials
Dr. Na Hyun Jo
Postdoctoral Researcher, Quantum System Accelerator
Lawrence Berkeley National Laboratory
We are currently living on the edge of the silicon age, characterized by the rapid growth of the semiconductor industry. Yet, a new class of materials destined to become as familiar as silicon is underway. These materials are so-called quantum materials and will be very important for future technologies such as quantum computers. In order to use quantum materials for future applications, it is essential to understand and control their electrical properties. In this colloquium, I will present synthesizing, understanding, and controlling a quantum material, WTe2…
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Fri Mar 12, 2021
Physics Colloquium: Dr. Ankit S. Disa, Max Planck Institute for the Structure and Dynamics of Matter
12:45 PM - 1:45 PM
zoom
Physics Colloquium
Structural control of quantum materials with light
Dr. Ankit S. Disa
Condensed Matter Dynamics Department
Max Planck Institute for the Structure and Dynamics of Matter
Quantum materials exhibit unique macroscopic phenomena with enormous technological potential, ranging from high-temperature superconductivity to topologically protected transport. Hence, at the forefront of condensed matter research is the goal of understanding and controlling their emergent behavior at the smallest length and time scales possible. Due to the strongly intertwined nature of electrons and the crystal lattice in these materials, manipulating the atomic structure allows one to tune interactions and create novel electronic and magnetic phases.…
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Wed Mar 31, 2021
Physics Colloquium: Prof. Keith Baker, Yale University
4:00 PM - 5:00 PM
zoom
Title TBA
Prof. Keith Baker
Yale University
Abstract forthcoming.…
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Wed Apr 7, 2021
Physics Colloquium: Ms. Lauren Chambers, ACLU of Massachusetts
4:00 PM - 5:00 PM
zoom
Title and abstract forthcoming
Ms. Lauren Chambers
ACLU of Massachusetts
All interested persons are invited to attend remotely—email physics@nd.edu for information.…
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Wed Apr 14, 2021
Physics Colloquium: Prof. Nico Orce, University of the Western Cape
4:00 PM - 5:00 PM
zoom
Physics Colloquium
Title and abstract forthcoming
Prof. Nico Orce
University of the Western Cape
Hosted by Prof. Brodeur
All interested persons are invited to attend remotely—email physics@nd.edu for information.…
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Wed Apr 28, 2021
Physics Colloquium: Prof. Louise Edwards, California Polytechnic State University
4:00 PM - 5:00 PM
zoom
Title and abstract forthcoming
Prof. Louise Edwards
California Polytechnic State University
All interested persons are invited to attend remotely—email physics@nd.edu for information.…
Posted In: Colloquia
Wed May 5, 2021
Physics Colloquium: Dr. Rebecca Thompson, Fermilab
4:00 PM - 5:00 PM
zoom
Title and abstract forthcoming
Dr. Rebecca Thompson
Head of Education and Public Engagement
Fermilab
Hosted by Prof. Brodeur
All interested persons are invited to attend remotely—email physics@nd.edu for information.…