A Half Century of Nonlinear Optics
22 Mar 2011 | Online Presentations | Contributor(s): Robert W. Boyd
In this talk, we first present a review of the development of the field of nonlinear optics, and we then survey some areas of recent research including quantum imaging and implications of the ability to control the group velocity of light.
Putting the Electron’s Spin to Work
14 Apr 2011 | Online Presentations | Contributor(s): Daniel Ralph
I will discuss recent progress in experimental techniques to control the orientations of nanoscale magnetic moments and electron spins, and to use these new means of control for applications. One powerful new capability arises from the fact that thin magnetic layers can act as filters for spins.
Nanoscale Spectroscopy and Plasmonics in Infrared
19 Apr 2012 | Online Presentations | Contributor(s): Mikhail Belkin
In this talk, I will present the results of two of our research projects. I will start with a simple technique for nanoscale mid-infrared spectroscopy that we have developed recently. Subwavelength resolution is achieved by detecting optical absorption through measuring local photothermal...
Nanoscale Electrothermal Energy Transport
12 Jul 2013 | Online Presentations | Contributor(s): Ali Shakouri
Thermoreflectance imaging is used to study Peltier cooling and Joule heating in devices with 800ps time and submicron spatial resolution. The ballistic heat conduction and the transition between energy and entropy transport in ultra short times and in thin film devices will be discussed. Finally...
The Secret Life of Electrons in High Temperature Superconductors
19 Jun 2013 | Online Presentations | Contributor(s): Erica W. Carlson
Physics of the Piano
12 Jul 2013 | Online Presentations | Contributor(s): Nicholas J. Giordano
Why does a piano sound like a piano? A similar question can be asked of virtually all musical instruments. A particular note, such as middle C, can be produced by a piano, a violin, and a clarinet. Yet, it is easy for even a musically untrained listener to distinguish between these instruments....
Catching Sunlight: Lessons from Photosynthesis
10 Jul 2013 | Online Presentations | Contributor(s): Sergei Savikhin
We will discuss the physics of early processes in photosynthesis revealed by ultrafast laser spectroscopy.
Quantum Band Engineering in III-nitride Semiconductors
12 Oct 2013 | Online Presentations | Contributor(s): Oana Malis
In this talk I will focus on our efforts to creatively exploit the unique properties of nano-structured III-nitride materials for novel light emitters and detectors in the currently under-developed near- and far-infrared ranges. Due to large electron effective mass, the nitride intersubband...
Sequencing a Genome by a Torrent of Ions: How an Old pH-Meter Got Its Groove Back
11 Apr 2014 | Online Presentations | Contributor(s): Muhammad A. Alam
The ability to read the book of life, written in the genome of an organism, has been one of the most exciting development of our time. The first version of human genome was announced circa 2000 and it took a decade of industrial-scale collaboration and billions of dollars of funding. Today, we do...
Strain Engineering of 2D Crystals
08 Oct 2014 | Online Presentations | Contributor(s): Bennett Goldberg
Two-dimensional materials are flexible, transparent, compatible with living systems, and can enable new devices and physics based on their unique properties. One unique property is the ability of 2D crystals a single atom thick to undergo massive amounts of strain without failure. Since strain...
Optically Probing the Nanoarchitecture of Cells and Tissues
19 Mar 2015 | Online Presentations | Contributor(s): Steven L. Jacques
This seminar presents our current work on using light to probe the nanoarchitecture (1-1000 nm) of cells and tissues. In particular, our experiments with SHG and holographic imaging of angular scattering of photons explore the structure of collagen fibers. Our work with confocal reflectance...
Incorporation of Studio Exercises for Physics Instruction at all Levels
11 Dec 2014 | Online Presentations | Contributor(s): Christopher M. Sorensen
In this talk I will give examples of studio activities from all three and observations with regard to how well this form of instruction works. I will also discuss problems incurred with regard to class size and time limitations. My goal is to encourage my audience to implement studio instruction...
Of Soot and Sunflowers
16 Dec 2014 | Online Presentations | Contributor(s): Christopher M. Sorensen
In this talk I will describe some of my researches into soot and other aggregate structures; an unlikely journey of discovery to find fractal structures with non-Euclidian dimensionality, gel networks of graphene that tenuously span space and common Fibonacci themes between spirals, sunflowers...
Integrated Imaging: Creating Images from the Tight Integration of Algorithms, Computation, and Sensors
21 Apr 2015 | Online Presentations | Contributor(s): Charles Addison Bouman
This talk presents some examples of state-of-the-art integrated imaging systems based on computed tomography (CT), transmission electron microscopy (STEM), synchrotron beam imaging, optical sensing, and scanning electron microscopy (SEM). For each of these examples, we also explore their use and...
Teaching Writing in Introductory Physics: the Good, the Bad, and the Revision
21 Apr 2015 | Online Presentations | Contributor(s): Scott Bonham
Written communication is an important skill in almost every field, including science and engineering. Over the last five years I have been evaluating different approaches for teaching and supporting development of technical writing skills. A common approach is providing students with written...
Progress in Superconducting Qubits
04 May 2015 | Online Presentations | Contributor(s): Robert F. McDermott
I will review progress in the field, with a focus on recent work in Wisconsin in the areas of decoherence and quantum measurement. I will discuss efforts to identify and suppress the dominant source of qubit dephasing, and I will describe a new approach to scalable, high-fidelity qubit...
Women and Physics
13 May 2015 | Online Presentations | Contributor(s): Laura McCullough
A discussion of some of the issues surrounding women's participation in physics. What comes with being of the feminine persuasion in a physics world? What hinders women's participation in physics? What helps? Why is it important? The fun and occasional fury of...
Teaching Science with Science Fiction
13 May 2015 | Online Presentations | Contributor(s): Kelly McCullough, Laura McCullough
Science fiction is one possible tool for increasing engagement in science classrooms, as well as offering opportunities for modeling scientific thinking, illustrating points of scientific interest, and addressing reading and writing standards for classroom content. Join Laura and Kelly McCullough...
Single Molecule Imaging in Live Cells
28 Aug 2015 | Online Presentations | Contributor(s): Kenneth Ritchie
Bacteria, such as Escherichia coli and Caulobacter crescentus, are the most studied and perhaps best-understood organisms in biology. The advances in understanding of living systems gained from these organisms are immense....
Finding Fake Videos With Physics
18 Feb 2016 | Online Presentations | Contributor(s): Rhett Allain
In case you haven’t noticed, the internet is full of videos. Some of these videos are about cats and some about interesting physics topics. You might be surprised to find that some of these online videos are fake (but hopefully you aren’t surprised). But how can you tell if a video is...
Tracking Energy Flow From the Nano to Mesoscale with Ultrafast Nanoscopy
22 Mar 2016 | Online Presentations | Contributor(s): Libai Huang
In this talk, I will discuss our recent efforts on elucidating multi-scale energy transfer, migration, and dissipation processes with simultaneous femtosecond temporal resolution and nanometer spatial resolution. We have combined/correlated ultrafast spectroscopy with high spatial resolution...
Oxide Systems – An Answer to the Qubit Problem?
08 Mar 2016 | Online Presentations | Contributor(s): Sudhakar Yarlagadda
One can produce new oxide-based devices by exploiting their tunability, rich physics, and coupling between the various degrees of freedom (such as charge, lattice, spin, etc.). We propose that oxide-based double quantum dots with only one electron (tunneling between the dots) can be regarded as a...
Ultrafast Optical Measurements of Spin Polarization in Semiconductors
29 Mar 2016 | Online Presentations | Contributor(s): Vanessa Sih
n this talk, I will describe optical techniques that can measure the magnitude and direction of spin-orbit fields and electrically-generated spin polarization in non-magnetic semiconductors and the modification of the electron spin precession frequency in a bulk semiconductor using an applied...
Piezotronics in 2D Piezoelectric Semiconductors
01 Apr 2016 | Online Presentations | Contributor(s): Wenzhuo Wu
Monolayer MoS2 and other TMDCs have been theoretically predicted to exhibit piezoelectricity due to the strain induced lattice distortion and associated ion charge polarization, suggesting possible applications of these 2D nanomaterials in nano-scale electromechanical devices that take advantage...
Quantum Measurement Backaction: From Atoms to Optomechanics
13 Oct 2016 | Online Presentations | Contributor(s): Mukund Vengalattore
The act of measurement has profound consequences on a quantum system. As such, the evolution of a quantum system can be influenced and even controlled through the continuous measurement of its properties. I will describe our studies on such measurement-induced dynamics in systems ranging from...
Complex Oxides and the Philosopher’s Stone
26 May 2016 | Online Presentations | Contributor(s): Shiram Ramanathan
In this talk I will discuss the topic of insulator-metal transitions in strongly correlated oxides, their control via disorder, orbital occupancy and electric fields and challenges these systems pose to our contemporary understanding of emergent phenomena in ionic lattices.
Tailoring Biomass to Fit the Biofuels Pipeline
10 Oct 2016 | Online Presentations | Contributor(s): Maureen McCann, Nicholas C. Carpita
Second-generation biofuels will be derived from lignocellulosic biomass using biological catalysts to convert the carbon in plant cell wall polysaccharides to ethanol or other biofuels. The Center for Direct Catalytic Conversion of Biomass to Biofuels (C3Bio) is a DOE-funded Energy Frontier...
Prospects for Using Magnetic Insulators in Spintronics
29 Sep 2016 | Online Presentations | Contributor(s): Mingzhong Wu
This presentation consists of two parts, which together will provide some perspective on the future of using magnetic insulators in spintronics. The first part will touch on the feasibility of using magnetic insulators, in particular, Y3Fe5O12 and BaFe12O19, to produce pure spin currents...
The Epithelial-Mesenchymal Transition Its role in metastasis? Can Theory Help Cancer Biology?
19 Oct 2016 | Online Presentations | Contributor(s): Herbert Levine
In order to spread from the primary tumor to distant sites, cancer cells must undergo a coordinated change in their phenotypic properties referred to as the "epithelial-to-mesenchymal" transition. We have studied the nonlinear genetic circuits that are responsible for this...
Optical Hyperspace: Light in Metamaterials with Hyperbolic Dispersion
03 Nov 2016 | Online Presentations | Contributor(s): Evgenii Narimanov
The composites with opposite signs of the dielectric permittivity in two orthogonal directions, known as the hyperbolic metamaterials, represent a new "universality class" of optical media, with the light behavior which is qualitatively different from that in either metals or...
Photonic Structures with Topological Robustness: from Classical to Quantum
09 Jan 2017 | Online Presentations | Contributor(s): Mohammad Hafezi
In this talk, I demonstrate how similar physics can be observed for photons; specifically, how various quantum Hall Hamiltonians can be simulated in an optical platform. I report on the first observation of topological photonic edge state using silicon-on-insulator technology and our recent...
Topological Spintronics: from the Haldane Phase to Spin Devices
31 Jan 2017 | Online Presentations | Contributor(s): Nitin Samarth
e provide a perspective on the recent emergence of “topological spintronics,” which relies on the existence of helical Dirac electrons in condensed matter. Spin‐ and angle‐resolved photoemission spectroscopy shows how the spin texture of these electronic states can be engineered using...
How 10 Years of Education Research Invalidated 40 Years of My Assumptions -- a personal conversion
08 May 2017 | Online Presentations | Contributor(s): David E. Pritchard
I shall describe an on-campus pedagogy that helps students to become more expert. Then I’ll describe how research, development, online learning and MOOCs might be combined to spread better learning universally.
Systems and Software for Quantum Computing
10 May 2017 | Online Presentations | Contributor(s): Travis S. Humble
In this talk, we define some of the system-level challenges facing the development of quantum computing systems as well as software-based approaches that can be used to overcome them. Following a brief overview of the state of the art, we present recent advances in the modeling and simulation of...
Weakly Ionized Plasmas for Reconfigurable RF Systems
10 May 2017 | Online Presentations | Contributor(s): Sergey Macheret
The presentation discusses properties of ionized gases (plasmas), such as those used in fluorescent lights, from the standpoint of their potential application to tunable and reconfigurable radio-frequency (RF) electronics: antennas, resonators, filters, etc. Plasmas have important advantages in...
Forces That Govern Life: On the Way to Understanding Intermolecular Interactions
20 Jul 2017 | Online Presentations | Contributor(s): Lyudmila V. Slipchenko
This talk will overview our recent work on the Effective Fragment Potential (EFP) method. EFP is a model potential designed for describing non-covalent interactions. The absence of fitted parameters and a natural partitioning of the interaction energy into Coulomb, polarization, dispersion, and...
Novel Vertically Aligned Nanocomposite (VAN) Designes: Oxide-Oxide Systems and Beyound
07 Sep 2017 | Online Presentations | Contributor(s): Haiyan Wang
The talk focuses on a set of hybrid materials in vertically aligned nanocomposite form with unique functionalities for device applications, including magnetoresistance materials, multiferroics, exchange bias, metamaterials for plasmonics and photonics, high density magnetic storage, high...
Quantum Optical Simulation of Complex Physical Hamiltonians
23 Oct 2017 | Online Presentations | Contributor(s): Alexander V. Sergienko
The rapidly expanding research activity on quantum computing is ultimately an outgrowth of the profound Feynman’s observation that only quantum systems are capable to efficiently simulate other quantum systems. The goal of quantum simulation is therefore to find simple quantum systems...
The Hunt for Non-Abelian Statistics
23 Oct 2017 | Online Presentations | Contributor(s): Yuli Lyanda-Geller
Search for non-Abelian statistics is driven both by the quest for a deeper understanding of nature and by prospects to eliminate the sensitivity of conventional quantum bits to the environment, opening a path for fault-tolerant quantum computing. The transformation of non-Abelions upon...
Magnetic Ordering on the Surface of a Topological Crystalline Insulator
27 Oct 2017 | Online Presentations | Contributor(s): Herbert A. Fertig
Topological crystalline insulators (TCI's) are a class of materials which can support non-trivial band topology protected by crystalline symmetry. Using analytic and numerical methods, we study the effect of bulk magnetic impurities on a model of (Sn,Pb)Te alloys which are...
Cavity Quantum Atom Optics: From Laser Cooled Atoms to Active Nano-Photonics
08 Feb 2018 | Online Presentations | Contributor(s): Mahdi Hosseini
In this talk I present results from the MIT experiment demonstrating coherent manipulation of atomic and optical states based on cQED light-atom interactions. Moreover, I present our ongoing effort at Purdue to realize similar quantum phenomena at the single photon level using chip-scale...
Bimetric Theory of Fractional Quantum Hall States
29 Nov 2017 | Online Presentations | Contributor(s): Andrey Gromov
In this talk, I will motivate and describe the recently developed bimetric theory of fractional quantum Hall states. This effective theory includes the Chern-Simons theory that describes the topological properties of the fractional quantum Hall states and an action a la bimetric gravity that...
Ultrafast Microscopy of Energy and Charge Transport
21 Dec 2017 | Online Presentations | Contributor(s): Libai Huang
In my talk, I will focus on our recent progress on visualization of exciton and charge transport in solar cell materials.
Understanding and Optimizing Exploratory Hydrothermal Reactions
22 Jan 2018 | Online Presentations | Contributor(s): Alex Norquist
In this work, an alternative approach that uses machine-learning algorithms trained on reaction data to predict reaction outcomes for the crystallization of templated vanadium selenites is demonstrated. Archived ‘dark’ reactions, both failed and successful attempts at hydrothermal...
Scaling Down the Laws of Thermodynamics
30 Apr 2018 | Online Presentations | Contributor(s): Christopher Jarzynski
Thermodynamics provides a robust conceptual framework and set of laws that govern the exchange of energy and matter. Although these laws were originally articulated for macroscopic objects, nanoscale systems often exhibit “thermodynamic-like” behavior – biomolecular motors...
Diffraction-Free Space-Time Wave Packets
30 Apr 2018 | Online Presentations | Contributor(s): Hasan Esat Kondakci
In this talk, I will discuss a novel family of diffraction-free ultrafast light pulses that are localized both in time and one transverse dimension. Such pulses, dubbed space-time wave packets, are a result of ‘classically-entangled’ spatio-temporal spectra corresponding to more...
A Lightning Introduction to Non-equilibrium Statistical Physics
30 Apr 2018 | Online Presentations | Contributor(s): Christopher Jarzynski
A brief and birds eye introduction to non-equilibrium statistical physics. This tutorial is organized around the 1st and 2nd laws of thermodynamics. It begins with brief review how the 1st and 2nd laws apply to macroscopic systems in the context of old fashion 19th century thermodynamics with...
Q-systems: Discrete Integrability and Cluster Algebras
14 May 2018 | Online Presentations | Contributor(s): Rinat Kedem
I’ll introduce a family of remarkable recursion relations, originally found in the context of the Bethe ansatz of generalized Heisenberg modules and quantum groups. I will reconsider this system as a discrete integrable system in its own right, and show some of the remarkable properties...
Quantum Effects in Electromagnetics and Computational Electromagnetics
20 Jun 2018 | Online Presentations | Contributor(s): Weng Cho Chew
In this talk, we begin by discussing quantum effects related to electromagnetics, such as spontaneous emission, Casimir force, quantum transport in devices, and quantum dissipations. Many of these effects have strong bearing on the future of quantum technology development. ...
From Driven Systems to Topological Quantum Machines: 2d Floquet and Topological Energy Pumping
21 Jun 2018 | Online Presentations | Contributor(s): Gil Refael
In my talk I will show how applying multiple periodic drives to a quantum system could increase its dimensionality, and may even realize a multidimensional topological phases for zero-dimensional systems. Particularly, a spin-1/2 particle, driven by two elliptically-polarized light beams could...
Novel III-Nitrides Materials for Infrared Optoelectronics: Growth, Structure and Properties
26 Sep 2018 | Online Presentations | Contributor(s): Oana Malis
I will describe our recent work to understand, model, and control the fundamental mechanisms of light absorption and electrical transport in nitride nanostructures. Special attention is given to the relationship between growth, structure, and optical properties in lattice-matched AlInN/GaN and...
Indirect Dissociative Recombination of Light Ions
29 Oct 2018 | Online Presentations | Contributor(s): Roman Čurík
Dissociative recombination (DR) is a process is which a free electron with a positive kinetic energy is captured by a molecular ion while breaking one or several chemical bonds,e− + AB+ → A + B .This is a very efficient chemical process, but is rarely described in chemical textbooks....
DFT Studies of Spin Orbit Coupling in Spintronics Materials
29 Oct 2018 | Online Presentations | Contributor(s): Ruqian Wu
In this talk, I will discuss how to effectively imprint the exchange and spin orbit coupling (SOC) of adatoms and newly discovered van der Waals (vdW) two-dimensional (2D) magnetic materials into graphene and topological materials to realize the quantum spin Hall effect or the...
Quantum Hall Transitions: Exact Results, Conjectures, and Numerical Tests
07 Nov 2018 | Online Presentations | Contributor(s): Ilya Gruzberg
In this talk I will review a number of recent results, analytical as well as numerical, on critical behavior near the integer quantum Hall transition and its cousins in other symmetry classes. The results include exact properties of the multifractal spectrum of critical wave functions obtained...
Topological Superconductivity and Majorana Bound State in Fe-based Superconductors
12 Nov 2018 | Online Presentations | Contributor(s): Hong Ding
In this talk I will report our recent discoveries of topological superconductivity and Majorana bound state in Fe-based superconductor Fe(Te, Se). We have obtained convincing ARPES evidence of superconducting topological surface state of Fe(Te, Se) single crystal with Tc ~ 14.5K. By using...