Particle-Hole Character of the Higgs and Goldstone Modes in Strongly Interacting Lattice Bosons
Authors: Di Liberto M., Recati A., Trivedi N., Carusotto I., Menotti C.
Autors Affiliation: [Di Liberto, M.; Recati, A.; Carusotto, I.; Menotti, C.] INO CNR BEC Ctr, I-38123 Povo, Italy and Univ Trento, Dipartimento Fis, I-38123 Povo, Italy.
[Recati, A.] Ludwigs Maximillian Univ Munchen, Arnold Sommerfeld Ctr Theoret Phys, D-80333 Munich, Germany.
[Trivedi, N.] Ohio State Univ, Dept Phys, Columbus, OH 43210 USA.
Abstract: We study the low-energy excitations of the Bose-Hubbard model in the strongly interacting superfluid phase using a Gutzwiller approach. We extract the single-particle and single-hole excitation amplitudes for each mode and report emergent mode-dependent particle-hole symmetry on specific arc-shaped lines in the phase diagram connecting the well-known Lorentz-invariant limits of the Bose-Hubbard model. By tracking the in-phase particle-hole symmetric oscillations of the order parameter, we provide an answer to the long-standing question about the fate of the pure amplitude Higgs mode away from the integer-density critical point. Furthermore, we point out that out-of-phase symmetric oscillations in the gapless Goldstone mode are responsible for a full suppression of the condensate density oscillations. Possible detection protocols are also discussed.
Journal/Review: PHYSICAL REVIEW LETTERS
Volume: 120 (7) Pages from: 073201-1 to: 073201-6
More Information: INSULATOR TRANSITION; OPTICAL LATTICES; QUANTUM GAS; ATOMS; TEMPERATURE;KeyWords: insulator transition; optical lattices; qunatum gas; atoms; temperatureDOI: 10.1103/PhysRevLett.120.073201Citations: 2data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2020-07-05References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here