The physics department has several active research areas ranging from the most abstract theoretical physics, to quantum properties of materials, to computational physics, to experiments involving many different kinds of advanced equipment (lasers, microscopes, spectrometers, cryostats, ultra-high vacuum, computer clusters, particle accelerators, etc.). In addition, there are many interdisciplinary activities and several collaborations with other departments at Lehigh and elsewhere.
This page highlights some research activities in the department, and the work of faculty members who are currently looking to add graduate students to their research groups over the next few years. This page is meant as a quick source of information for students who are interested in applying to the department’s graduate program and who want to have a short overview of possible advisors.
Please see the physics main site and the websites of individual faculty members for more in-depth information.
Theoretical Condensed Matter Physics
Prof. Bitan Roy and Prof. Chinedu Ekuma and their research groups are working on fundamental theoretical analysis and computational modeling of several special condensed matter systems, such as two-dimensional layered materials, interfaces, semiconductors, and insulators.
The Ekuma’s group uses cutting-edge data-driven materials informatics and machine learning techniques to develop the structure of the next generation of quantum materials. The research group is developing and implementing computational methods that are able to predict several important material properties (magnetism, conductivity, ability to interact with light, etc.) before they are synthesized.
Prof. Bitan Roy‘s research group works on quantum field theory and on the development of new theoretical models understandings of how topology (certain geometrical aspects of quantum-mechanical wavefunctions) can determine key properties of new materials. The group’s activities include the investigation of strongly coupled quantum phases like magnetism and superconductivity, and other exotic quantum properties.
Experimental Condensed Matter Physics and Photonics
The research groups of Prof. Volkmar Dierolf and Prof. Ivan Biaggio use light-matter interaction and 93different types of Lasers, together with a few other techniques, to study several types of physical effects and materials with future technological applications such as light-emitting displays, solar energy harvesting, optical telecommunication, and quantum information sciences.
The Dierolf research group investigates how specific atoms (typically so-called rare earth atoms like Europium or Erbium) can enable new features in new semiconductors (like the ability to act as light-emitting diodes in different spectral colors), or be used to store quantum information.
The Biaggio group is doing research on organic semiconductors (crystals consisting of organic molecules in which light absorption creates moving bundles of energy called excitons), and the quantum-mechanics of entangled spin-states in those materials. The group is also investigating the integration of organic small molecules into state-of-the art technologies that control light propagation on a microchip, towards creating the photonics equivalent of electronic microchips.
Ultracold Atoms and Quantum Processors
The research group of Prof. Ariel Sommer utilizes gases of atoms trapped in vacuum and cooled to ultra-low temperatures to investigate the behavior of strongly interacting collections of quantum particles. In their experiments, they cool gases of lithium-6 atoms to near absolute zero using laser light. As fermions, lithium-6 atoms obey the Pauli exclusion principle and therefore mimic the behavior of electrons in solids, and also of neutrons in neutron stars. By studying the dynamics of atomic gases, the Sommer group aims to provide insight into the underlying physics of electron transport in strongly correlated materials. A current project focuses on implementing a multi-region optical box trap that will allow controlled studies of atomic gases out of equilibrium, which provides fundamental insight into strongly correlated systems and a model of material devices such as normal-superconductor junctions.
High Energy Physics – Experimental Nuclear Physics
Prof. Rosi Reed and Prof. Anders Knospe investigate the new physics that arises when two large atomic nuclei or other particles collide in large accelerators, in particular the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. There are reasons to believe that the state of matter created in such high energy collisions, called a quark-gluon plasma, is the same that existed a few microseconds after the Big Bang.
Prof. Reed is an expert in the particle jets that are emitted out of the quark-gluon plasma formed after the high-energy collisions of atomic nuclei, and in their use to image the structure of the quark-gluon plasma. Prof. Knospe‘s research focuses on heavy-quark bound states that are found after such collisions and that can serve as very special probes, providing key information to determine the properties of the matter formed in these collisions. Their group contributes to the STAR and sPHENIX experiments at RHIC. They led the construction of the sPHENIX Event Plane Detector and have contributed to the construction, commissioning, and operation of several other detector subsystems at both experiments.
High Energy Physics – String Theory and Cosmology
Prof. Timm Wrase and Prof. Sera Cremonini examine a variety of questions about the nature of gravity, the structure of spacetime and the early evolution of the universe. Prof. Cremonini uses the tools of string theory to explore the connection between gravitational theories and quantum field theories, and gain insights into fundamental properties of black holes. Some of these techniques can also be applied to understand quantum phases of nature relevant to condensed matter physics. Prof. Wrase investigates the historical evolution of the universe, including such effects as inflation and dark energy, as well as more mathematical aspects of string theory.
Biophysics – from soft condensed matter to living cells
Prof. Daniel Ou-Yang, Prof. Aurelia Honerkamp-Smith, and Prof. Dimitrios Vavylonis work on the experimental investigation of complex fluids and biological systems, and on the theoretical modeling of cellular mechanisms. Prof. Ou-Yang is an expert in colloids and the statistical physics of macromolecule diffusion, and his research group works on advanced optical imaging and micro-characterization tools such as optical tweezing and “optical bottles” to study materials at the interface between living and nonliving systems.
Prof. Honerkamp-Smith uses microscopy and neutrons to probe the micro- and nanoscale behavior of lipid membranes and microscopic flow in these membranes, gaining new insights into the way many living cells sense flow in order to regulate important physiological functions.
Prof. Vavylonis uses computer simulations and mathematical models to study the physical principles governing the function and organization of living cells. In this way the group develops a new understanding of the intricacies with which a cell can organize its contents or change its shape by complex self-assembly and self-disassembly of its internal structures. The primary interest lies in the cytoskeleton, a crucial component of cells that forms various structures responsible for mechanical integrity, shape maintenance, and motor-driven movement.