3 papers
quant-ph2020
Generalization of group-theoretic coherent states for variational calculations
Tommaso Guaita, Lucas Hackl, Tao Shi +2
We introduce new families of pure quantum states that are constructed on top of the well-known Gilmore-Perelomov group-theoretic coherent states. We do this by constructing unitari…
quant-ph2020
Geometry of variational methods: dynamics of closed quantum systems
Lucas Hackl, Tommaso Guaita, Tao Shi +3
We present a systematic geometric framework to study closed quantum systems based on suitably chosen variational families. For the purpose of (A) real time evolution, (B) excitatio…
cond-mat.quant-gas2019
Gaussian time dependent variational principle for the Bose-Hubbard model
Tommaso Guaita, Lucas Hackl, Tao Shi +3
We systematically extend Bogoliubov theory beyond the mean field approximation of the Bose-Hubbard model in the superfluid phase. Our approach is based on the time dependent variat…