We investigate a species selective cooling process of a trapped SU(N ) Fermi gas using entropy redistribution during adiabatic loading of an optical lattice. Using high-temperature expansion of the Hubbard model, we show that when a subset N A < N of the single-atom levels experiences a stronger trapping potential in a certain region of space, the dimple, it leads to improvement in cooling as compared to an SU(N A ) Fermi gas only. We show that optimal performance is achieved when all atomic levels experience the same potential outside the dimple and we quantify the cooling for various N A by evaluating the dependence of the final entropy densities and temperatures as functions of the initial entropy. Furthermore, considering 87 Sr and 173 Yb for specificity, we provide a quantitative discussion of how the state selective trapping can be achieved with readily available experimental techniques.

Mechanical pressure controls the structural, electric, and magnetic order in solid-state systems, allowing tailoring of their physical properties. A well-established example is ferroelastic ferroelectrics, where the coupling between pressure and the primary symmetry-breaking order parameter enables hysteretic switching of the strain state and ferroelectric domain engineering.Here, we study the pressure-driven response in a nonferroelastic ferroelectric, ErMnO 3 , where the classical stress−strain coupling is absent and the domain formation is governed by creation− annihilation processes of topological defects. By annealing ErMnO 3 polycrystals under variable pressures in the MPa regime, we transform nonferroelastic vortex-like domains into stripe-like domains. The width of the stripe-like domains is determined by the applied pressure as we confirm by three-dimensional phase field simulations, showing that pressure leads to oriented layer-like periodic domains. Our work demonstrates the possibility to utilize mechanical pressure for domain engineering in nonferroelastic ferroelectrics, providing a lever to control their dielectric and piezoelectric responses.