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تسجيل مستخدم جديدInteraction-driven Lifshitz transition with dipolar fermions in optical lattices
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نشر من قبل
Erik Gerardus Cornelis Petrus van Loon
تاريخ النشر
2016
مجال البحث
فيزياء
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English
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Anisotropic dipole-dipole interactions between ultracold dipolar fermions break the symmetry of the Fermi surface and thereby deform it. Here we demonstrate that such a Fermi surface deformation induces a topological phase transition -- so-called Lifshitz transition -- in the regime accessible to present-day experiments. We describe the impact of the Lifshitz transition on observable quantities such as the Fermi surface topology, the density-density correlation function, and the excitation spectrum of the system. The Lifshitz transition in ultracold atoms can be controlled by tuning the dipole orientation and -- in contrast to the transition studied in crystalline solids -- is completely interaction-driven.
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