Quantum Optics with Atomic Ensembles and Arrays

Regents Of The University Of Michigan - Ann Arbor, Ann Arbor MI

Investigators

Abstract

Advances in data processing and learning algorithms are paving a road that will transform our society through improvements in technologies such as artificial intelligence. In parallel, scientists are exploiting the far-reaching implications of quantum mechanics to dramatically improve the capabilities of computers and telecommunication networks. At the heart of quantum computing and quantum telecommunications networks is a purely quantum feature called entanglement, in which unique states of matter and radiation are created. The research team will explore new methods for efficiently and effectively creating such entanglement. To do so they will use optical fields to create arrays of atoms which interact with quantum radiation fields. By creating controllable environments of atom arrays using optical trapping fields, the research team will study the underlying mechanisms responsible for atom-atom and atom-field entanglement. The team will also employ different theoretical models to help explain the experimental observations. As a result this project will lead to a deeper understanding of the interaction between atoms and quantum fields that can serve as a springboard for the development of novel methods for achieving scalable generation and distribution of entanglement. During this project students will be trained in state-of-the-art techniques in experimental physics, optics, electronics, and computer-based data acquisition. The PIs will investigate two types of atomic systems aimed at quantum networking: the first one employing an array of single-atom qubits for processing, storage, and atomic qubit mapping into photons, and the second one using qubits encoded in ensembles of atoms. Both of these approaches allow for Rydberg-based generation of multi-qubit entangled states, second-timescale entanglement storage within ground hyperfine manifolds, and efficient generation of atom-light entanglement. Atoms will be confined using either optical tweezers or optical lattices that provide state-insensitive potentials for the atomic qubit states. This will allow for controlled preparation of strongly-interacting, many-atom quantum state superpositions, and their storage on timescales of seconds. Using these systems, the PIs will explore new approaches to generating and distributing atom-light entanglement. The research team will focus on elucidating connections between fundamental light-matter interactions and functionalities relevant to quantum networks; e.g., they will study the role of the dipole-dipole interaction processes in atom-field mapping, and spatial and temporal superradiance in atomic arrays. They will also study the validity and applicability of the rotating-wave approximation and the Weisskopf-Wigner approximation, while considering problems related to "mixed' superradiance where competition between unphased and phase-matched superradiance occurs when the atoms are excited to a phased, collective state containing more than a single excitation. 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.