Shopping cart

close

Past Events

Event Date Summary
Condensed Matter Seminar: Jie Gao, Missouri University of Science and Technology (University of Missouri – Rolla) Thu. May 11th, 2017
11:30 am-12:30 pm

Jie Gao

Missouri University of Science and Technology (University of Missouri – Rolla)

Tailoring light-matter interaction with metamaterials and metasurfaces

Metamaterials and metasurfaces with designed subwavelength nanostructures exhibit intriguing electromagnetic phenomena, such as negative refraction, invisible cloaking, sub-diffraction imaging, near-zero permittivity and hyperbolic dispersion. In this talk, I will present our recent work on tailoring light-matter interaction with metamaterials and metasurfaces, including the realization of enhanced spontaneous emission, ultrasensitive molecule detection, strong plasmon-phonon interaction, optical vortex generation and full-color metasurface hologram. These results present opportunities and challenges in understanding new physics of light-matter interaction in those artificially structured optical materials and realizing many unprecedented applications in nanophotonics.

CANCELED: Maosheng Miao, California State University Northridge,Simulate to discover: from new chemistry under high pressure to novel two-dimensional materials Mon. April 24th, 2017
12:45 am-1:45 am

CANCELED. Will be rescheduled.

Simulate to discover: from new chemistry under high pressure to novel two-dimensional materials

 

Maosheng Miao

Department of Chemistry and Biochemistry

California State University Northridge, California 91330, USA

 

The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry, rooted in the atomic shell structure. Within compounds, Group I elements, for example, invariably assume the +1 oxidation state, and their chemical properties differ completely from those of the p-block elements.

David Pace, General Atomics, San Diego, The Fast and the Furious: Energetic Ion Transport in Magnetic Fusion Devices Wed. April 19th, 2017
12:45 am-1:45 am

The Fast and the Furious: Energetic Ion Transport in Magnetic Fusion Devices

D.C. Pace and the DIII-D National Fusion Facility Team

General Atomics, P.O. Box 85608, San Diego, CA 92186-5608, USA

David Pace

Nuclear fusion has the potential to be an energy source that powers society without generating greenhouse gases or high-level radioactive waste. The tokamak approach to controlled nuclear fusion employs a toroidally-shaped magnetic field configuration to confine plasmas at temperatures beyond 200 million K (20 keV). Future reactors aim to utilize the deuterium-tritium fusion reaction due to its favorable cross-section,
Louis F. Piper, Binghamton University, Shining new light on old problems in lithium ion batteries Mon. April 17th, 2017
12:45 am-1:45 am

Shining new light on old problems in lithium ion batteries

 

Louis Piper

Binghamton University, State University of New York

 

Improving the energy storage and release of lithium ion battery is largely limited to the cathode (positive electrode).  Commercial high capacity LIBs employ Ni-rich layered oxides (derived from LiCoO2) as cathodes.  In these systems, the reversible energy storage capacity is limited to 1 Li+ per transition metal (i.e. Co3+/4+ redox couple).  However, only 2/3 of Li+ per redox couple are typically intercalated due to capacity retention issues with fast cycling and high voltages. 

Nandini Trivedi, The Ohio State University, Novel magnetic phases in spin-orbit coupled oxides Mon. April 10th, 2017
12:45 pm-1:45 pm
Novel magnetic phases in spin-orbit coupled oxides
Nandini Trivedi,
 
Department of Physics, The Ohio State University
 

Abstract: I will discuss puzzles about magnetism in some of the simplest oxide materials with a single electron in the d-orbital.  Starting from a microscopic model of a Mott insulator with both spins and orbitals, I will obtain the effective magnetic Hamiltonian and provide insights into the experimental puzzles. 

Nate Stern, Northwestern University, Monolayer Semiconductor Opto-Electronics: Controlling Light and Matter in Two-Dimensional Materials Mon. April 3rd, 2017
12:45 pm-1:45 pm

Monolayer Semiconductor Opto-Electronics: Controlling Light and Matter in Two-Dimensional Materials

Nathaniel Stern

Department of Physics and Astronomy, Northwestern University

The discovery of monolayer two-dimensional semiconductors of atomic-scale thickness presents a new two-dimensional landscape in which to play with the interaction between light and matter. These nanomaterials at the extreme limit of surface-to-volume ratio exhibit rich optical phenomenology such as layer dependent bandgaps and degenerate, but distinct, valley-polarized excitonic states. The unique features of atomically-thin materials suggest that these layered systems can be exploited to achieve new regimes of light-matter interactions.

Paul Kelly, University of Twente, Turning up the heat in first principles Quantum Spin Transport Wed. March 22nd, 2017
12:45 pm-1:45 pm

Turning up the heat in first principles Quantum SpinTransport

 Paul J. Kelly

Faculty of Science and Technology and MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands

 

The spin Hall angle (SHA) is a measure of the efficiency with which a transverse spin current is generated from a charge current by the spin-orbit coupling and disorder in the spin Hall effect (SHE). In a study of the SHE for a Pt|Py (Py=Ni80Fe20) bilayer using a first-principles scattering approach,

No Seminar, APS March Meeting and Spring Break Mon. March 13th, 2017
1:00 am-1:00 am
Francesca F. Serra, Johns Hopkins University, Control of liquid crystals through topography for optics and assembly Mon. February 27th, 2017
12:45 pm-1:45 pm
Control of liquid crystals through topography for optics and assembly 
Dr. Francesca Serra 

Physics and Astronomy 

Johns Hopkins University
 
Soft materials are a promising tool to explore controllable energy landscapes. Liquid crystals, in particular, combine reconfigurability, unique optical properties and the possibility of directing their self-assembly via the bounding surfaces. I will show, for example, how smectic-A liquid crystals under different boundary conditions create microlens arrays made of focal conic defects or light guides in an aqueous solution. Focal conic domains act as gradient refractive index lenses that can be assembled and ordered exploiting topographical cues.
Hamza Balci, Kent State University, A Single Molecule Approach to Study Protein, Small Molecule, and G-Quadruplex Mon. February 20th, 2017
12:45 pm-1:45 pm

A Single Molecule Approach to Study Protein, Small Molecule, and  G-Quadruplex Interactions

Hamza Balci

Kent State University, Physics Department, Kent, OH

 

G-quadruplex (GQ) structures are non-canonical nucleic acid secondary structures that form in guanine-rich segments of the genome, most prominently at telomeres. In addition, several hundred thousand potential GQ forming sequences have been identified in human genome, with particularly higher frequency at promoter regions. When GQ structures (GQs) form at telomeres, they cap chromosome ends and are involved in stabilizing these vulnerable regions. Also, GQs have been shown to regulate transcription and translation level gene expression when they form in promoter regions of DNA and 5′-UTR of RNA,

Saw-Wai Hla, Ohio University, Operating Individual Quantum Molecular Machines Mon. February 6th, 2017
12:45 pm-1:45 pm

Operating Individual Quantum Molecular Machines

Saw-Wai Hla

 Department of Physics & Astronomy, Ohio University, OH 45701, USA

and

Nanoscience and Technology Division, Argonne National Laboratory, IL 60439, USA.

E-mail: hla@ohio.edu , URL: www.phy.ohiou.edu/~hla

 

A recent emergent research direction is the development of complex molecular machines suitable to operate on solid surfaces. Biological machines have the sizes from tens of nanometers to a few microns –a range where classical machine concepts hold while artificially designed molecular machines can be in the size range of a few nanometers or less,

Mike Boss, NIST, Physics and Impact of Quantitative Magnetic Resonance Imaging Mon. January 30th, 2017
12:45 pm-1:45 pm

Physics and Impact of Quantitative Magnetic Resonance Imaging

Michael Boss,

Applied Physics Division
National Institute of Standards and Technology, Boulder, CO

Each year, millions of U.S. patients are scanned using Magnetic Resonance Imaging (MRI), costing billions of dollars.  The resultant images are typically qualitative, limiting the ability to compare results across patients, time, and scanners. However, a suite of physical parameters (e.g., relaxation times, diffusion coefficients) are interrogable with magnetic resonance, enabling quantitative imaging biomarkers (QIBs). QIBs can provide threshold values for disease diagnosis, allow meaningful measurement of longitudinal change for evaluating treatment response,

Lucile Savary (MIT) — Michelson Postdoctoral Prize Lecturer Fri. January 27th, 2017
12:45 pm-1:45 pm

Quantum Loop States in Spin-Orbital Models on the Honeycomb and Hyperhoneycomb Lattices

In the quest for quantum spin liquids, the challenges are many: neither is it clear how to look for nor how to describe them, and definitive experimental examples of quantum spin liquids are still missing. In this talk I will show how to devise a realistic model on the honeycomb lattice whose ground state realizes Haldane chains whose physical supports fluctuate, hence naturally providing the hallmark “fractional excitations” of quantum spin liquids. When taken to the three-dimensional hyperhoneycomb lattice, the ground state becomes a full-fledged symmetry-enriched U(1) quantum spin-orbital liquid,

Lucile Savary (MIT) — Michelson Postdoctoral Prize Lecturer Tue. January 24th, 2017
11:00 am-12:00 pm

Quantum Spin Ice

Recent work has highlighted remarkable effects of classical thermal fluctuations in the dipolar spin ice compounds, such as “artificial magnetostatics.” In this talk, I will address the effects of terms which induce quantum dynamics in a range of models close to the classical spin ice point. Specifically, I will focus on Coulombic quantum spin liquid states, in which a highly entangled massive superposition of spin ice states is formed, allowing for dramatic quantum effects: emergent quantum electrodynamics and its associated emergent electric and magnetic monopoles. I will also discuss how random disorder alone may give rise to both a quantum spin liquid and a Griffiths Coulombic liquid–a Bose glass-like phase.

Michael Snure, AFRL, Two dimensional BN an atomically thin insulator, substrate, and encapsulation layer from growth to application Mon. January 23rd, 2017
12:45 pm-1:45 pm

Two dimensional BN an atomically thin insulator, substrate, and encapsulation layer from growth to application

Michael Snure

Air Force Research Laboratory, Sensors Directorate, Wright Patterson AFB, OH

Since free standing graphene was found in 2004, there has been an explosion of research on atomically thin two dimensional (2D) materials based isolated sheets of layered van der Waals solids.  The spectacular electrical and thermal transport properties of graphene generated a great deal of hype making it a heavily researched material for ultra-high-speed electronics; however, strong interaction with conventional 3D substrates and the lack of a band gap has proven to degrade properties and limit its usefulness in these devices. 

Lucile Savary (MIT) — Michelson Postdoctoral Prize Lecturer Mon. January 23rd, 2017
4:15 pm-5:15 pm

A New Type of Quantum Criticality in the Pyrochlore Iridates

The search for truly quantum phases of matter is one of the center pieces of modern research in condensed matter physics. Quantum spin liquids are exemplars of such phases. They may be considered “quantum disordered” ground states of spin systems, in which zero point fluctuations are so strong that they prevent conventional magnetic long range order. More interestingly, quantum spin liquids are prototypical examples of ground states with massive many-body entanglement, of a degree sufficient to render these states distinct phases of matter. Their highly entangled nature imbues quantum spin liquids with unique physical aspects,


Scroll To Top