Introduction to Quantum Computing (CMSC457/PHYS457, Spring 2022)
An introduction to the concept of a quantum computer, including algorithms that outperform classical computation and methods for performing quantum computation reliably in the presence of noise. As this is a multidisciplinary subject, the course will cover basic concepts in theoretical computer science and physics in addition to introducing core quantum computing topics.
Advanced Topics in Theory of Computing; Classical and Quantum Codes (CMSC858Q/PHYS889C, Spring 2022)
The course will cover topics in classical and quantum coding theory from the unified perspective of protecting information in classical communication and supporting fault-tolerant computations in quantum computers. Topics in classical codes include: Reed-Solomon codes, codes on algebraic curves, Reed-Muller codes, polar codes, rank metric codes. Topics in quantum codes include: stabilizer codes, CSS codes, GKP codes, polynomial codes, toric code.
Research Interactions in Mathematics (RIT on Quantum Information) (MATH489/689, Spring 2022)
In this seminar, we are interested in all aspects of research at the intersection between quantum information science and mathematics. Goals for talks include:
Studying recent research results in quantum information from a mathematical angle;
Finding examples (old and new) in which existing tools from mathematics can be adapted for application in quantum information;
Studying quantum algorithms for mathematical problems.
https://quics.umd.edu/people/carl-miller
Special Problems in Advanced Physics; Seminar in Quantum Physics, Information, and Technology (PHYS798Q, Spring 2022)
Friday Quantum Seminars. 1 credit.
"Giant Artificial Atoms and Waveguide QED"
Abstract: Models of light-matter interaction with natural atoms typically invoke the dipole approximation, wherein atoms are treated as point-like objects compared with the wavelength of their resonant driving fields. In this talk, we present a demonstration of “giant artificial atoms” realized with superconducting qubits in a waveguide QED architecture. The superconducting qubits couple to the waveguide at multiple, well-separated locations. In this configuration, the dipole approximation no longer holds, and the giant atom may quantum mechanically self-interfere.
A semidefinite programming based approach to near-term quantum advantage and device certification
Abstract: Semidefinite Programming (SDP) is a class of convex optimization programs with vast applications in control theory, quantum information, combinatorial optimization, machine learning and operational research. In this talk, I will discuss how SDP can be used to address two major challenges in quantum computing research: near-term quantum advantage and device certification.
Pseudo-Gauge Field in Dirac/Weyl Materials
Abstract: In solid materials, electrons are usually described by the non-relativistic Schrodinger equationsince electron velocity is much slower than the speed of light. However, the relativisticDirac/Weyl equation can emerge as a low-energy effective theory for electrons in certainmaterials. These systems are dubbed “Dirac/Weyl materials” and provide a tunable platformto test quantum relativistic phenomena in table-top experiments. Owing to the linear-inmomentum form, a variety of physical fields, e.g.
Enhancement of superconductivity with external phonon squeezing
Abstract: Squeezing of phonons due to the nonlinear coupling to electrons is a way to enhance superconductivity. In this talk I will present a model of quadratic electron-phonon interaction in the presence of phonon pumping and an additional external squeezing. I will show that the interference between the two driving sources can lead to a stronger electron-electron attraction. This allows for the enhancement of superconductivity, which is shown to be maximal on the boundary with the dynamic lattice instabilities caused by driving.
Precision-enhanced displacement measurements using correlated photon pairs
Abstract: Split detection is a standard experimental scheme for measuring positional displacements. In a typical setup, a laser beam is reflected from the object being probed and then sent to a photodetector that is split into left (L) and right (R) halves: the normalized difference signal (R-L)/(R+L) is then proportional to the object’s horizontal displacement. The maximum precision achievable using this method is limited by the inverse of the beam width.
Excursions at the Interface of Topological Phases of Matter and Quantum Error Correction
Dissertation Committee Chair: Professor Maissam Barkeshli
Committee:
Professor Sankar Das Sarma
Professor Jay Deep Sau
Professor Michael Gullans
Professor Mohammad Hafezi