Self-generated quantum gauge fields in arrays of Rydberg atoms

• Published in: New journal of physics Vol. 24; no. 2; pp. 23017 - 23035
• Main Authors: Ohler, Simon, Kiefer-Emmanouilidis, Maximilian, Browaeys, Antoine, Büchler, Hans Peter, Fleischhauer, Michael
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.02.2022; Institute of Physics: Open Access Journals
• Subjects: Amplitudes; Approximation; Arrays; correlated hopping; Density; density-dependent Peierls phase; effective gauge fields; Energy costs; General Physics; Magnetic fields; Phase transitions; Physics; Rydberg atoms; Spin-orbit interactions; vortex to Meissner phase transition; Vortices; vortex; modulation; Rydberg atoms; critical phenomena; density-dependent Peierls phase; wave; mean field approximation; yield; induced; effective gauge fields; potential; dimension; correlated hopping; energy; gauge; costs; density; transverse; hopping; 1; spin; vortex to Meissner phase transition; gauge field theory; atom; density dependence; excited state; ground state
• ISSN: 1367-2630; 1367-2630
• DOI: 10.1088/1367-2630/ac4a15

Abstract As shown in recent experiments (Lienhard et al 2020 Phys. Rev. X 10 021031), spin–orbit coupling in systems of Rydberg atoms can give rise to density-dependent Peierls phases in second-order hoppings of Rydberg spin excitations and nearest-neighbor repulsion. We here study theoretically a one-dimensional zig-zag ladder system of such spin–orbit coupled Rydberg atoms at half filling. The second-order hopping is shown to be associated with an effective gauge field, which in mean-field approximation is static and homogeneous. Beyond the mean-field level the gauge potential attains a transverse quantum component whose amplitude is dynamical and linked to density modulations. We here study the effects of this to the possible ground-state phases of the system. In a phase where strong repulsion leads to a density wave, we find that as a consequence of the induced quantum gauge field a regular pattern of current vortices is formed. However also in the absence of density–density interactions the quantum gauge field attains a non-vanishing amplitude. Above a certain critical strength of the second-order hopping the energy gain due to gauge-field induced transport overcomes the energy cost from the associated build-up of density modulations leading to a spontaneous generation of the quantum gauge field.