Quantum properties of a binary bosonic mixture in a double well
Author: Pere Mujal
Two condensates of identical bosons trapped in a double well, called a Bosonic Josephson Junction, present interesting quantum phenomena like Josephson oscillations and self-trapping  that have been observed experimentally . The ground state of the system depends on atom-atom interactions and on the height of the barrier between the two sites of the double well and can host relevant quantum spatial correlations . What would happen if we had two bosonic species instead of one?
The physics of a binary mixture of Bose-Einstein condensates trapped in a double-well potential is captured by a two-component two-site Bose-Hubbard model . A crucial aspect of this system is that it can host relevant entangled many-body states, e.g., Schrödinger catlike states. The richness of the binary-mixture in a double-well is the possibility of having not only spatial entanglement but also quantum correlations between the two species. Taking the atom-atom interactions within each species and among the two species as variable parameters, the many-body properties of the ground state are fully characterized by means of quantum information tools, such as the Schmidt gap or the von Neumann entropy complemented by usual many-body techniques like the computation of the condensed fractions.
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