The Spring 2017 colloquia will be held in the lobby of the Physical Sciences Complex unless otherwise noted

Each week during the semester, the Department of Physics invites faculty, students and the local community to hear prominent scientists discuss intriguing physics research. The Spring 2017 colloquia will be held Tuesdays in the Physical Sciences Complex lobby at 4:00 p.m. (preceded by light refreshments at 3:30 p.m.)

Parking is available in the Regents Drive Parking Garage (PG2). An attendant will direct visitors within the garage. Additionally, a free ShuttleUM bus runs between the College Park Metro Station and Regents Drive at about eight-minute intervals.

For further information, please contact the Physics Department at 301-405-5946 or email This email address is being protected from spambots. You need JavaScript enabled to view it..

January 31
Lisa Manning, Syracuse University 
Hosted by: Chris Jarzynski

Jamming in Biological Tissues

Biological tissues involved in important processes such as embryonic development, lung function, and cancer progression have recently been shown to be close to a disordered fluid-to-solid transition. However, existing theories cannot explain jamming transitions in confluent tissues, where there are no gaps between cells and the packing density is always unity. I will discuss a new theoretical framework that predicts a critical rigidity transition in biological tissues identified by an experimentally accessible structural order parameter, with diverse potential applications in asthma, cancer, metamaterials and mechanical topological insulators


February 7
John Mather, NASA

From the Big Bang to the end of the universe, and how we’ll learn more with the James Webb Space Telescope

The James Webb Space Telescope, planned for launch in October 2018, will be the most powerful space telescope ever built. It will open new territories of astronomy, with observations ranging from the first stars, galaxies, and black holes, to the growth of galaxies, to the formation of stars and planetary systems, to the evolution of planetary systems and the conditions for life here on Earth, and perhaps elsewhere.  I will show how we have learned about the history of the universe, how the Big Bang is a completely misleading name for the infinite expanding universe, and what new telescopes are being built now. I will illustrate with simulations of the formation of galaxies from the primordial material, and the possible evolution of the solar system through planetary orbit migration. The JWST telescope mirror has been assembled and the instrument module has been completely tested. After more tests at Goddard, the telescope/instrument combination will travel to Houston for cryo-vacuum tests in Chamber A in 2017. I will show the design of the observatory and discuss the opportunities for future observers to prepare to use it.


February 14
No colloquium



February 21
Ed Ott, University of Maryland

Emergent Behavior in Large Systems of Many Coupled Oscillators

Large systems of many coupled dynamical units are of crucial interest in a host of physical, biological and technological settings. Often the dynamical units that are coupled exhibit oscillatory behavior. The understanding and analysis of these large, complex systems offers many challenges. In this talk I will introduce this topic, give some examples, and describe a technique for analyzing a large class of problems of this type. The results I will discuss will reduce the complicated, high dimensional, microscopic dynamics of the full system to that or a low dimensional system governing the macroscopic evolution of certain 'order parameters'. This reduction is exact in the limit of large systems, i.e., N going to infinity, where N is the number of coupled units, and can be employed to discover and study all the macroscopic long term behaviors of these systems.

February 28
Carr Lecture
PHYS Room 1412
Stuart Parkin, IBM/Max Planck Institute 
Hosted by: Rick Greene/Chris Lobb

Beyond charge currents: spin and ion currents for future computing Technologies

The era of computing technologies based on charge currents is coming to an end after more than than 40 years of exponential increases in computing power that have been largely based on shrinking devices in two dimensions.  A new era of “Beyond charge!” will evolve over the next decade that will likely be based on several new concepts. Firstly, devices whose innate properties are derived not from the electron’s charge but from spin currents and from ion currents.  In some cases new functionality will arise that can extend charge based devices but in other case fundamentally new computing paradigms will evolve.   Secondly, devices will inevitably become three-dimensional: novel means of constructing devices, both from bottom-up and top-down, will become increasingly important.  Thirdly, bio-inspired devices that may mimic the extremely energy efficient computation systems in the biological world are compelling.   In this talk I will discuss possible spintronic and ionitronic devices and how they may lead to novel computing technologies.

March 7

Ignacio Cirac, Max Planck Institute

Tensor Networks:  A quantum information perspective to many-body physics

The theory of entanglement offers a new perspective to view many-body quantum systems. In particular, systems in thermal equilibrium and with local interactions contain very little entanglement, which allows us to describe them efficiently, circumventing the exponential growth of parameters with the system size. Tensor Networks offer such a description, where few simple tensors contain all the information about all physical properties. In this talk I will review some of the latest results on entanglement and tensor networks, and explain some of their connections to quantum computing, condensed matter, and high-energy physics.

March 14
Cancelled due to snow; rescheduled for April 25
March 21
Spring Break No colloquium
No colloquium


March 28

Steve Fetter, University of Maryland
Hosted by: Steve Rolston

Science and National Security in the White House

From March 2009 to August 2012, and from July 2015 to January 2017, Steve Fetter took a leave of absence from the University of Maryland to work in the White House Office of Science and Technology Policy, first as assistant director at-large, then as director of OSTP’s environment and energy division, and most recently as director of its national security and international affairs division.  Dr. Fetter will discuss what it is like to work as a scientist in the White House, review key accomplishments of the Obama Administration at the intersection of science and national security, and discuss the challenges that lie ahead for the Trump Administration.


April 4
Andrea Cavalleri, Max Planck Institute
Hosted by: 

Max Planck Institute for the Structure and Dynamics of Matter, Hamburg GERMANY 


In this talk, I will discuss how coherent electromagnetic radiation at infrared and TeraHertz frequencies can be used to coherently rearrange atoms within the crystal lattice of a solid. The motion of atoms is large, and the lattice dynamics is discussed in terms of nonlinear phononics. We control metal insulator transitions, magnetic phenomena, superconductivity and ferroelectricity dynamically. I will also discuss how femtosecond x-ray beams from free electron lasers are integral to these studies, and are used to image structures during these non-equilibrium processes.



April 11
Ashvin Vishwanath, Harvard
Hosted by: Mohammad Hafezi

Topology, Duality and Entanglement in Quantum Matter 

I will review recent developments in solid state physics that exposed the role of topology and entanglement in quantum many particle systems. This has led to the prediction of entirely new strongly interacting phases and provided insights into existing states. In this program, dualities have played an important role in the describing strongly interacting quantum systems.  Finally I will discuss ongoing attempts to extend the domain of topological quantum phases to non-equilibrium situations. 


April 18

Hosted by: 

Teach-In on Science and Activism


As part of our week of civic engagement culminating at the March for Science , we will have a series of speakers, including:

Steven Rolston, UMD Physics, “A Climate Change Primer”

Will Thomas, AIP, “Science Embroiled in Politics: A Brief Historical Tour.”

Melinda Baldwin, AIP : “Golden goose or golden fleece? Attacks on federal science funding during the Cold War.”

Katarina Keane, UMD History and Center for Global Migration Studies, "Immigrants and Immigration Policy as the Building Blocks of Scientific Discovery”

Steve Fetter, UMD Public Policy, “How to be a Policy Entrepreneur"

April 25
Ellen Williams, University of Maryland

Scientific Innovation and the Energy System 

Extracting useful heat and work from energy sources is essential to human civilization, and the energy infrastructure that has developed to meet the world’s needs is immense, complex and weighted with legacy technology. Today issues of energy equity, environment, climate change and climate adaptation are transforming the context in which the energy system is evolving. Scientific innovation and its use in new energy technologies is key to meeting energy needs in a world of increasing demand and increasing constraints.

Fortunately, the U.S. infrastructure of research and development has created a wealth of tools and approaches that allow new progress. The development of computational methods, data analytics, nanoscience, photonics and systems optimization are just a few of the new opportunities supporting innovations in energy technologies.

Examples of high-potential energy innovation will be drawn from the portfolio of the Advanced Research Projects Agency – Energy. Serious choices about research priorities must balance the scale of the potential impact, what new scientific approaches are available to change existing approaches, and the barriers that might prevent a new technology from reaching application.

May 2



May 9
Tilman Esslinger, ETH Zurich Institute 
Hosted by: Mohammad Hafezi

A Supersolid of Matter and Light 

The concept of a supersolid state is paradoxical. It combines the crystallization of a many-body system with dissipationless flow of the atoms it is built of. This quantum phase requires the breaking of two symmetries, the phase invariance of a superfluid and the translational invariance to form the crystal. We experimentally studied two forms of supersolids: i) a lattice supersolid, breaking a discrete translational symmetry. This bosonic lattice model features competing short- and long-range interactions, and we observed the appearance of four distinct quantum phases—a superfluid, a supersolid, a Mott insulator and a charge density wave. The system is based on an atomic quantum gas trapped in an optical lattice inside a single high-finesse optical cavity [1]. ii) Most recently, we succeeded in realizing a supersolid breaking a continuous translational symmetry. This symmetry emerges from two discrete spatial ones by symmetrically coupling a Bose-Einstein condensate to the modes of two optical cavities [2].


Upcoming Events


Wed, Jun 28, 2017 11:00 am - 12:00 pm


Thu, Jun 29, 2017 11:00 am - 12:00 pm