Physics Department Colloquium

Abstract: The atomic nucleus emerges from interacting quantum particles called quarks and gluons, but how this happens remains unknown. This might be elucidated with quantum-level "images" of their position, orbital motion, spin alignment, and entanglement. I will describe recent and upcoming experiments at the Thomas Jefferson Laboratory that use a high-intensity, high-energy electron beam to probe a wide range of nuclear targets, from polarized lithium to lead.

Abstract: Superconducting quantum computers, once scaled up, could solve problems intractable to even the largest classical supercomputers, but better superconducting qubits are needed before this can occur. Superconducting qubit coherence is currently limited both by cryogenic low-power dielectric loss and by large temporal fluctuations due to strongly-coupled defects.

Abstract: In classical physics, unbounded (or "up-side-down")
potentials do not allow for a stable ground state. As a consequence,
unbounded potentials have often been dismissed as not viable for
proper unitary quantum theories. Historically, we have learned that
the quantum world often contradicts dearly held beliefs based on
classical physics. By contrast, mathematics has been recognized as a
good guide even when classical intuition fails.  In this talk, I will
use well-developed mathematics to explore physical systems with

Abstract: Highlights from research done on the National Ignition Facility (NIF) laser through the Discovery Science program will be presented. Plasma nuclear reactions relevant to stellar nucleosynthesis and nuclear reactions in high energy astrophysical scenarios are being studied. [1] Equations of state (EOS) at very high pressures (0.1-100 TPa or 1-1000 Mbar) relevant to planetary cores, brown dwarf interiors, and white dwarf envelopes are being measured on NIF, and show that the level of ionization can significantly affect the compressibility of the sample.

Abstract: Recent experiments at SLAC demonstrated beam-driven plasma acceleration with accelerating gradients in excess of 150 GeV/m. That’s nearly 10,000 times the accelerating gradient produced by RF cavities in the SLAC linac! Plasma accelerators are a promising technology for future ultra-high energy colliders and were identified by the P5 Panel as a path toward 10 TeV collisions. In this talk, I’ll review the physics of nonlinear plasma wakefield acceleration. What makes the plasma bubble nearly-ideal for electron acceleration?

The Higgs boson was discovered in 2012 by the ATLAS and CMS experiments at the world’s most powerful particle collider, the Large Hadron Collider (LHC) in Geneva, Switzerland. This particle plays a unique role in fundamental physics. It gives all of the known elementary particles, including itself, their masses.

Abstract: This presentation describes space weather impacts and their economic and societal costs. Modern technological society is characterized by a complex set of interdependencies across its critical infrastructures. These are vulnerable to the effects of intense geomagnetic storms and solar disturbances. Strong currents flowing in the ionosphere can disrupt and damage Earth-based electric power grids and contribute to the accelerated corrosion of oil and gas pipelines.

Abstract: Words of Richard Feynman “What I cannot create, I do not understand” inspire r

Abstract: The guided transmission of optical waves is essential for modern applications in communication, information processing, and energy systems. Traditionally, light guiding in structures like optical fibers has been predominantly achieved through total internal reflection. In periodic structures, a range of other physical mechanisms can also facilitate optical wave transport.