Phase separation of binary condensates in harmonic and lattice potentials

We propose a modified Gaussian ansatz to study binary condensates, trapped in harmonic and optical lattice potentials, both in miscible and immiscible domains. The ansatz is an apt one as it leads to the smooth transition from miscible to immiscible domains without any {\em a priori} assumptions. In optical lattice potentials, we analyze the squeezing of the density profiles due to the increase in the depth of the optical lattice potential. For this we develop a model with three potential wells, and define the relationship between the lattice depth and profile of the condensate.