CAREER: Interfacing Spins with Photons - Quantum Many-Body Physics with Non-Local Interactions

Stanford University, Stanford CA

Investigators

Abstract

The forces between particles are typically local, decreasing in strength with increasing distance. Locality restricts the forms of matter that we find in nature - and harness in technology - to be far less varied than what the laws of physics theoretically allow. For example, while quantum mechanics permits information to be stored in correlations shared between distant particles, it is more natural to store information in individual local "bits." In this project, to explore the full potential of quantum mechanics, this team will engineer forces that act non-locally, letting photons carry information between massive particles at light speed. Potential impacts include discovering new states of matter and enabling new approaches to computation and precision sensing. Experiments will be conducted in a model system composed of laser-cooled atoms, which can be understood abstractly as spins or qubits. Effectively non-local interactions will be induced by strongly coupling the atoms to light in an optical resonator. This team will engineer and probe a variety of spin models, including an Ising model featuring a phase transition in computational complexity. They will examine how the structure of interactions influences quantum correlations and dynamics. They will also entangle atoms in a controlled fashion, comparing coherent and dissipative approaches to harnessing atom-light interactions for many-body quantum state preparation. High-resolution imaging will enable detailed characterization of quantum states. The project includes an educational component with two key objectives. One educational objective is to develop activities introducing high-school students to cutting-edge topics in quantum science, with an eye towards broadening participation in physics. Undergraduate students will develop and convey these activities, thereby also serving as mentors and role models. A second objective is to assess the impact of applying a student-centered, active learning approach in an advanced undergraduate course (statistical mechanics), in lieu of traditional lectures where students watch the professor derive complex equations on a blackboard. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.