Speaker
Dr
Christian Schilling
(University of Oxford)
Description
For $N$ hard-core bosons on an arbitrary lattice with $d$ sites and independent of additional interaction terms we prove that the hard-core constraint itself already enforces a universal upper bound on the Bose-Einstein condensate given by $N_{max}=(N/d)(d-N+1)$. This bound can only be attained for one-particle states $|\varphi\rangle$ with equal amplitudes with respect to the hard-core basis (sites) and when the corresponding $N$-particle state $|\Psi\rangle$ is maximally delocalized. This result is generalized to the maximum condensate possible within a given sublattice. We observe that such maximal local condensation is only possible if the mode entanglement between the sublattice and its complement is minimal.
Author
Dr
Christian Schilling
(University of Oxford)
Co-authors
Mr
Felix Tennie
(University of Oxford)
Prof.
Vlatko Vedral
(University of Oxford)
