Are micro black holes potentially created in high-energy proton collisions? Is nature supersymmetric? We also work on the development of future collider experiments, with a focus on potential muon colliders. Students in our group build upgrades for the CMS experiment, operate the detector during data-taking, and analyze data to search for new particles and look for deviations from known processes. Computational work is an essential component of a PhD in this group. Past experience with coding is a plus, but in any case, students will be expected to develop coding competency in their first year with the group. Graduate students learn about and apply different particle detection techniques and statistical analysis methods, including machine learning. We open new avenues by developing smart search strategies to not overlook any exciting corner where new physics could show up. The group’s hardware work is centered around charged particle detection with the CMS Tracker. The group has helped build, install, and now operates a new instrument as part of the CMS detector at CERN that measures inclusively the rate of particles produced in proton-proton collisions at the LHC to derive the luminosity that is essential to all particle searches. We are now working towards an upgrade of the tracker for the High-Luminosity LHC, working areas that include sensor R&D, module production, data acquisition, and real-time tracking. Prototype sensors and data acquisition systems are tested in our laboratory at UT and in test beams at Fermilab, Los Alamos, and CERN. We collaborate with people at universities and labs all around the world, and students will typically spend some time in Switzerland.

If you’re interested in the CMS group, contact any of the PIs:

Stefan Spanier

Tova Holmes

Lawrence Lee

The accelerator physics program supports a diverse range of research projects aimed at addressing Grand Challenges [ref link] in beam physics while optimizing the performance of the SNS high-power accelerator. Key challenges include:

How can we increase beam power by orders of magnitude without increasing particle losses?

How can we predict and control the beam at the level of individual particles?

Research in this area requires both theoretical and experimental investigations into the dynamics of high-intensity charged particle beams, with a focus on multi-particle interactions and collective effects that drive nonlinear beam dynamics. Significant emphasis is placed on development of the tools and techniques to enable future higher power accelerators, including next generation injection technologies, novel non-interceptive beam measurement methods, laser-based beam diagnostics, and advanced high-dimensional, high-dynamic-range diagnostics.

Research at SNS is conducted using both the SNS accelerator and the Beam Test Facility (BTF), a functional replica of the SNS accelerator’s front-end, dedicated primarily to R&D. Graduate research opportunities span experimental, computational, and theoretical domains, providing all students with hands-on experience in designing and executing experiments on the SNS and/or BTF accelerators.  More information on the SNS R&D program can be found at neutrons.ornl.gov.

Interested candidates should contact UT adjunct faculty Sarah Cousineau or Nick Evans.

Sarah Cousineau

Nick Evans

Our group focuses on Escherichia coli, whose relatively simple cellular organization makes it possible to bridge the gap between molecular-scale processes and whole-cell behavior. A long-term goal of our research is to understand how a cell organizes and reproduces itself from the collective behavior of its molecular components.

Our current research addresses the following questions:

How is bacterial DNA organized, compacted, and segregated in the cell?

How do cell-division proteins self-assemble into functional molecular structures?

How are cell division and DNA replication coordinated during the cell cycle?

We approach these questions through a combination of quantitative experiments and physics-based modeling. Experimentally, we use live-cell fluorescence microscopy, including imaging at or near the single-molecule level, together with microfluidic devices that allow us to follow individual cells over many generations. We develop and fabricate micro- and nanoscale structures for these experiments using cleanroom facilities, including those available through Oak Ridge National Laboratory (ORNL). We also develop quantitative image-analysis and computational methods to extract physical information from microscopy data. To interpret the experiments, we use numerical modeling and concepts from statistical mechanics, polymer physics, soft-matter physics, stochastic processes, and elasticity. Projects, therefore, provide opportunities for students with experimental, computational, or theoretical interests, as well as for students who would like to combine several of these approaches.

For more information, visit our lab website or contact Jaan Männik. Motivated students interested in applying physics to fundamental problems in living systems are encouraged to inquire about research opportunities.

Jaan Männik

Prominent among these developments are the areas of (1) High Temperature Superconductors, with critical temperatures that have reached over 150 K and with exotic pairing properties, (2) Colossal Magnetoresistance Manganites, with changes in DC current of many orders of magnitude upon the application of small magnetic fields, and (3) Nanosystems, where quantum effects play a key role. Some members of the Condensed Matter Theory group carry out investigations in these fields and several related ones. The main tools to analyze models for these materials involve computational techniques, since typically there are no small parameters to guide a perturbative expansion, but analytical calculations are also performed. The broad area of investigations outlined in this paragraph is usually referred to as Strongly Correlated Electrons. This field of investigations is also much related with the popular area called Complexity, due to recently unveiled similarities between soft and hard materials.

The UT/Physics Department group working in this research context has a high international visibility, and publishes in prestigious journals such as Physical Review Letters, Science, Physics World, and others. For a list of recent publications see http://sces.phys.utk.edu. The group consists of two professors (Distinguished Professor E. Dagotto and Professor A. Moreo), and several students and postdocs. We receive the frequent visits of collaborators from the US and abroad.

A variety of clusters of PCs are available for the application of computational methods to the study of the materials described above. This includes clusters located at both UT and ORNL, and the combined number of PCs as of April 2005 was close to 300.

The group has a strong relation with the Theory Group of the Condensed Matter Sciences Division (CMSD) of Oak Ridge National Laboratory.

Elbio Dagotto

Adriana Moreo

We are currently developing a scintillator array for detecting gamma rays called HAGRiD, based on new generation scintillator material LaBr₃(Ce). A particular strength of the group is the tradition of use of digital data acquisition techniques. Students entering the group will be involved in both hardware development and cutting-edge nuclear physics experiments.

Our experiments are run at national user facilities such as the National Superconducting Cyclotron Laboratory at Michigan State University, with new experimental programs starting at TRIUMF in Canada, and Argonne National Laboratory in Illinois.

Decay of the most exotic nuclei

One main focus of our group is exploratory research on the most exotic nuclei that can be synthesized. We develop ultra-sensitive detection techniques, and then employ them in discovery experiments at very low production rates. We investigate phenomena that occur only in very unstable isotopes, for example, beta-delayed neutron emission using the VANDLE detector. Our expertise in digital electronics has allowed us to engage recently in the super-heavy element research program, a newly re-open nuclear physics frontier.

Direct reactions

Direct reaction techniques include transferring a single nucleon or multiple nucleons, knocking out a nucleon, or simply scattering a nucleus on a target, and are very sensitive to the structure of the nucleus. Recent developments have allowed these techniques to be used with beams of exotic nuclei, some of which are important to understand reactions in stars or in explosive scenarios, such as novae or supernovae.

Robert Grzywacz

Kate Jones

Miguel Madurga

Using the Spallation Neutron Source at ORNL as well as other intense neutron sources such NIST’s research reactor and the Institut Laue Langevin’s (Grenoble, France) high flux reactor, we address such experimental questions as the neutron electric dipole moment, the free neutron lifetime, and the details of parity violation in nuclear processes. The work involves a wide variety of techniques including charged and neutral particle detection, ultra-low temperature cryogenic system, polarized beams, etc. This work should appeal to experimentalists who enjoy hands on physics as well as broad theoretical ideas.

Further information is available online at: neutrons.ornl.gov.

Nadia Fomin

The main questions for this field are: What binds protons and neutrons into stable nuclei and rare isotopes? What is the origin of simple patterns in complex nuclei? When and how did the elements from iron to uranium originate? What causes stars to explode? The new and exciting frontier in nuclear theory lies in the description of rare and short-lived nuclei. These nuclei have unusual ratios of neutrons to protons. In this unique situation, important inter-nucleon interactions are isolated and amplified. The weak binding of neutron-to-proton asymmetric systems add additional flavor to the nuclear many-body problem. Exciting new properties are, e.g. neutron halos, proton radioactivity, and changes in shell structure.

The UT/ORNL nuclear theory group consists of Drs. D. J. Dean, G. Hagen, T. Papenbrock, several long- and short-term visitors, postdoctoral associates, and students. We investigate many aspects of the nuclear many-body problem with particular emphasis on rare isotopes. We employ microscopic methods (involving density functional theory, coupled cluster theory, Monte Carlo simulation, and shell model diagonalizations), and tackle theoretical challenges with pencil and paper, PCs, and the world’s most powerful supercomputers. We also apply our ideas to other many-body problems, e.g., to ultracold atom gases. For more details, please see the titles of our recent publications, and come to our seminar. The group has several international visitors each year, and collaborates with experimental nuclear physicists at UT and ORNL. A few potential projects are described below.

First-principles nuclear structure calculations with the coupled-cluster method

We are using the coupled-cluster methods for first-principles calculations of selected nuclei that are of current experimental and theoretical interest. Within this approach, a similarity-transformed Hamiltonian is constructed that decouples from few-particle few-hole excitations. The application of this method involves diagrammatic derivations, and a numerical implementation of the derived expressions. Students working in this area would actively participate in code development and calculations for relevant benchmark nuclei. The scientific questions we address relate to the role of three-nucleon forces in nuclei, and the evolution of shell structure in exotic nuclei.

Thomas Papenbrock

We study neutrino properties using the Spallation Neutron Source (SNS) at ORNL, a 1.3 GeV, 2 MW proton accelerator that produces the world’s most intense pulsed neutrino source. The COHERENT experiment made the first observation of Coherent Elastic Neutrino-Nucleus Scattering (CEvNS) and is now studying this process in detail. This is essentially an in-house experiment at the cutting edge of neutrino physics, providing graduate students with extensive hands-on experience in both software and hardware.

We are also looking for a graduate student interested in gaining hands-on experience working with ultra-pure materials for the LEGEND neutrinoless double-beta-decay experiment. The work will involve developing and characterizing ultra-radiopure materials, as well as extensive collaboration and communication with members of the large international LEGEND-1000 Collaboration.

Yuri Efremenko

Our research combines advanced experiments, physical modeling, and machine learning. Experimental approaches include neutron scattering with momentum, energy, and time resolution; optical Raman spectroscopy, including measurements under high pressure; x-ray scattering; and low-temperature electrical and magnetic measurements. Experiments are carried out both at UT and at major national user facilities, particularly Oak Ridge National Laboratory.

An increasingly important direction in our group is physics-informed machine learning and computational inference for quantum materials. We are interested not simply in using machine learning to predict experimental outcomes, but in developing methods that can extract microscopic interactions and effective Hamiltonians from complex experimental data, distinguish competing physical models, and help determine which measurements contain the information needed to resolve a scientific question.

Current and emerging graduate research opportunities include:

     • Raman spectroscopy of quantum materials, particularly spin-orbit-coupled and magnetic materials and their evolution under high pressure;

     • Machine learning and inverse problems in quantum materials, combining experimental scattering data, microscopic models, statistical inference, and modern ML methods;

     • Novel transport phenomena in quantum materials, with an emphasis on connecting unusual electronic response to microscopic and quantum-mechanical properties;

     • Quantum and frustrated magnetism, using neutron and optical spectroscopy together with computational modeling to understand emergent excitations, magnetic correlations, and nonequilibrium behavior.

Students may develop projects that are predominantly experimental, computational, or span both. We welcome students from physics, materials science, and related backgrounds who are interested in learning new experimental or computational techniques and in working across traditional disciplinary boundaries.

Yishu Wang

We have a strong team (Haidong Zhou, Jian Liu, Joon Sue Lee, and Wonhee Ko) working on quantum materials synthesis including bulk single crystal growth, thin film growth, and heterostructure deposition, physical properties characterization, evidencing the quantum phenomena, and manipulation of the quantum behavior for potential applications. We welcome highly motivated students to contribute to our efforts and enjoy the scientific adventure with us.

Zhou’s research interests are to discovery new materials possessing abnormal physical properties, such as geometrically frustrated magnetism showing quantum spin behaviors, multiferroicity, orbital ordering, and metal-insulator transitions. The strategies are to grow bulk single crystals of them using various methods including floating zone technique in image furnace, flux method, and chemical vapor transport method, and thereafter study them by x-ray scattering, low temperature and high magnetic field measurements, and neutron scattering measurements.

Liu’s projects span various topics, such as topology-correlation interplay, quantum critical phenomena, quantum magnetism, metal-insulator transition, and unconventional superconductivity. The focus is to identify, design, and create toy-model materials where we can tailor the dimensionality and the symmetry operations to capture fundamental physics of model Hamiltonians, such as the Hubbard model and Heisenberg model. This goal is achieved by exploiting advanced bottom-up synthesis technique, novel elastic strain engineering, multi-modal synchrotron x-ray scattering, and ultralow temperature high magnetic field measurements. In many cases, the observed unusual quantum phenomena also afford unparalleled functionalities for potential applications. Liu’s work involves broad collaborations within the department both experimentally and theoretically. Multiple positions are currently available for students to join Liu’s research on emergent phenomenain quantum condensed matters, which include atomically engineered quantum heterostructures and quantum materials.

Lee employs molecular beam epitaxy to synthesize high-quality thin films and nanostructures of quantum materials, by precise control over layer-by-layer growth in ultrahigh vacuum environment. His research group develops low-dimensional semiconductor systems, such as 1D nanowires, 2D electron gases, and networks of quantum wires by selective area growth, as well as topological materials including topological insulators and semimetals. His research extends to studies on quantum devices based on the grown quantum materials for unveiling fundamental quantum phenomena and exploring future device applications.

Ko’s research focuses on nanoscale to atomic-scale characterization of the quantum materials using novel microscopy techniques.

We welcome highly motivated students to contribute to our efforts and enjoy the scientific adventure with us.

Haidong Zhou

Jian Liu

Joon Sue Lee

Wonhee Ko

Current research spans several areas, including the development of quantum algorithms and applications, simulation of quantum many-body systems and lattice gauge theories, photonic and continuous-variable quantum computing, quantum machine learning, and methods for assessing the computational resources required for practical quantum advantage. The group also investigates quantum communication and networking, including entanglement distribution, quantum cryptography, quantum interference over optical fiber networks, and protocols for distributed quantum systems. In quantum sensing and metrology, we study how entanglement, squeezing, and other quantum resources can improve the precision of measurements and enable new sensing modalities.

Experimental research includes quantum optics, generation and detection of nonclassical and entangled light, single-photon detection, fiber-based quantum communication, and the development and characterization of quantum-network components and testbeds. Theoretical and computational projects range from fundamental quantum information and quantum optics to algorithms for near-term and fault-tolerant quantum computers.

Research is carried out at both the University of Tennessee, Knoxville (UTK) and Oak Ridge National Laboratory (ORNL), with opportunities for collaboration with scientists in academia, national laboratories, and industry. Projects are available for students with interests in theory, computation, or experiment, and several graduate research assistantship opportunities are anticipated.

quantum@tennessee.edu

Website: quantum.utk.edu

In this new phase nuclear matter no longer consists primarily of protons and neutrons, but instead consists of deconfined quarks and gluons in a state that mostly resembles a superfluid liquid. Experimentally, we are creating high temperature nuclear matter by colliding heavy nuclei (heavy ions) at very high energies (ultrarelativistic energies) at nuclear accelerators

Our future graduate students will work on the sPHENIX Collaboration at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory, Long Island, New York. In general, the RHIP group has two to four students involved in our research at different stages in their graduate studies, a post-doc, and two professors, Christine Nattrass and Ken Read.

Christine Nattrass

Ken Read