Dark Solitons with Majorana Fermions in Spin-Orbit-Coupled Fermi Gases
Yong Xu, Li Mao, Biao Wu +1 more
We show that a single dark soliton can exist in a spin-orbit-coupled Fermi gas with a high spin imbalance, where spin-orbit coupling favors uniform superfluids over nonuniform Fulde-Ferrell-Larkin-Ovchinnikov states, leading to dark soliton excitations in highly imbalanced gases. Above a critical spin imbalance, two topological Majorana fermions without interactions can coexist inside a dark soliton, paving a way for manipulating Majorana fermions through controlling solitons. At the topological transition point, the atom density contrast across the soliton suddenly vanishes, suggesting a signature for identifying topological solitons.
arXiv:1401.3777•Physical Review Letters•Sep 25, 2014•57 citations