Freiburg 2019 – wissenschaftliches Programm
FM 37.5: Talk
Dienstag, 24. September 2019, 15:00–15:15, 3042
Eigenstate Complexity of Interacting Bosons on a Lattice — •Lukas Pausch, Alberto Rodríguez, and Andreas Buchleitner — Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Hermann-Herder-Straße 3, D-79104 Freiburg, Germany
Multifractality has proven to be an efficient quantifier of the complexity of many-particle states in Fock space, and it has been used to expose ground state phase transitions [1,2]. In our present numerical study, we use multifractality to investigate Fock space complexity for the full set of eigenstates of the Bose-Hubbard Hamiltonian. We examine the evolution of the distribution of generalized fractal dimensions as a function of interaction strength and in relation to the behaviour of the energy spectrum. This analysis reveals that the eigenstate structure in Hilbert space changes drastically across the energy canvas for different values of the interaction. Furthermore, we investigate possible connections between multifractality and the emergence of quantum chaos.
 J. Lindinger, A. Buchleitner and A. Rodríguez, Phys. Rev. Lett. 122, 106603 (2019).
 D. J. Luitz, F. Alet and N. Laflorencie, Phys. Rev. Lett. 112, 057203 (2014).