SearcharxivSearch

arXiv subjects

Benno Bock

Publications and source records attributed to Benno Bock.

2 recordsLinked to original sources

Parton Mean-Field Theory of a Rydberg Quantum Spin Liquid induced by Density-Dependent Peierls Phases

We derive a parton mean-field Hamiltonian for Rydberg excitations on a honeycomb lattice with nearest and density-dependent, complex next-nearest neighbor hopping. Numerical results obtained from exact diagonalization of small systems have given indications for a ground state that is a chiral spin liquid (CSL) [Phys.Rev.Res. 5, 013157 (2023)]. Here we provide further evidence for this. Calculating the ground-state wavefunction self-consistently, we show that the mean-field Hamiltonian fulfills the requirements for a CSL ground state, resulting from a projected symmetry group classification and verify the expected twofold topological degeneracy on a torus. Furthermore we find very good overlap with the ground-state wavefunctions obtained by exact diagonalization of the original Hamiltonian.

cond-mat.quant-gas

Quantum-Noise Induced Localization and Motional Squeezing in a Rydberg Quantum Simulator

We investigate the interplay between mechanical forces and the internal-state dynamics of Rydberg excitations in atom-tweezer arrays. Dipole interactions between Rydberg atoms facilitate excitation spreading, but at the same time couple electronic (spin) degrees of freedom with motional (phonon) states. With increasing spin-phonon coupling, the growth dynamics of a cluster of excited Rydberg atoms changes from ballistic spreading to Bloch-like oscillations and eventually to Anderson-like localization. We show that these effects are caused by quantum fluctuations in the phonon field: The dynamics of a Rydberg cluster can be mapped to a single particle in a semi-infinite lattice subject to phonon-induced energy shifts. The mean-field contribution of this energy shift leads to a linear potential gradient, resulting into Bloch-like oscillations. In addition, quantum fluctuations of phonons create a random local potential causing a transition from a regime of Bloch oscillations to localization. The spin-phonon coupling leads furthermore to highly correlated and non-classical phonon states in the form of squeezed states of the position of the Rydberg atoms. Depending on the form of the dipolar interaction potential, either in- or out-of-phase correlated oscillations of atoms emerge.

cond-mat.quant-gas