Department of Physics & Astronomy
Welcome!
Our department is driven by an engaged faculty pursuing fundamental research and eager to develop the next generation of scientists.
Our physicists helped put our state on the periodic table, study multi-messenger astronomy and explosive stellar events, and search for new physics at CERN. They describe the properties of nuclei and neutrons and test the limits of superconductivity with new models and novel materials. They merge physics and biology at the cellular level with lab-on-a-chip devices. They’re building an interdisciplinary approach to lead transformative research on quantum materials and devices, information science, and artificial intelligence.
Our students have a breadth of research opportunities on campus, at nearby Oak Ridge National Laboratory, and at facilities all over the world to set them on the path to promising careers.
Department News
Colloquium Schedule
Pair Density Wave (PDW) States in a Magnetic Superconductor
October 14, 2024
Speaker: He Zhao, Florida State University
Host: Ruixing Zhang
Abstract
Under specific conditions, exotic Cooper pairing state can emerge with a non-uniform equilibrium order parameter, possessing a finite center-of-mass momentum. Such spatially dependent order parameters (ฮ๐(r)) can generically feature variations in either their amplitude or phase โ or a combination of both. Utilizing Spectroscopic Imaging Scanning Tunneling Microscopy (SI-STM), we’ve identified two primary PDW states in the iron pnictide superconductor, EuRbFe4As4 (ER-1144), a material that features co-existing superconductivity (Tc โ 37 kelvin) and magnetism (Tm โ 15 kelvin). In the ferromagnetic superconducting phase, the first type is characterized by a superconducting gap that has a long-range, unidirectional spatial modulation (๐ฅ๐~|๐ฅ0|cos(Qโr)) in the absence of any other translational symmetry breaking density-wave orders. The second type features an anisotropic Doppler energy shift in reciprocal space due to the phase winding (๐ฅ๐~|๐ฅ0|๐๐Qโr). In contrast, all the striking features are completely suppressed crossing the magnetic transition. Additionally, both PDW states are also impacted by an out-of-plane external magnetic field, evidenced by the Bogoliubov quasiparticle spectrum imaging. Our findings provide valuable insights into the intricate nature of the PDW states and the interplay between magnetism and superconducting order.
Gayane Vardoyan, University of Massachusetts Amherst
October 21, 2024
Speaker: Gayane Vardoyan
Host: George Siopsis
Abstract
TBA
PRX: What Kind of Papers We are Looking for?ย
October 28, 2024
Speaker: Yiming Xu, Physical Review X
Host: Haidong Zhou
Abstract
PRX is published by the American Physical Society, a nonprofit membership society of scientists. Its mission goal is to select around 250 *landmark* papers a year from all fields of physics and showcase them to a broad and multidisciplinary readership.
Is your paper a good match for PRX? Or asked differently, what papers qualify as *landmark* papers?
How do the PRX editors actually select such papers? Are such selections always accurate?
How can you, as an author, navigate PRXโs editorial and peer-review process effectively and get the most out of your interactions with the editors and referees?
I will use the talk to discuss with you how to answer these questions. Many of these questions do not have a black-and-white answer in the case of a single paper. Open-minded, reasoned, and constructive dialogues amongst the authors, the editors, and the referees are key to making each concrete process a meaningful and productive experience, and sometimes even a pleasure, for everyone.
