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Non-Hermitian skin effect, which refers to the phenomenon that an extensive number of eigenstates are localized at the boundary, has been widely studied in lattice models and experimentally observed in several classical systems. In this work, we predict that the dissipative ultracold fermions with spinorbit coupling can exhibit the non-Hermitian skin effect. We demonstrate this effect in a continuous model which has been implemented by the Hong-Kong group in a recent experiment. This skin effect is robust against the variation of external parameters and can be detected by the dynamic sticky effect. Our work paves the way for studying novel physical responses of non-Hermitian skin effect in quantum systems.

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We performed angle-resolved photoemission spectroscopy (ARPES) studies of the electronic structure of the nematic phase in LaFeAsO. Degeneracy breaking between the dxz and dyz hole bands near the Γ and M point is observed in the nematic phase. Different temperature dependent band splitting behaviors are observed at the Γ and M points. The energy of the band splitting near the M point decreases as the temperature decreases while it has little temperature dependence near the Γ point. The nematic nature of the band shift near the M point is confirmed through a detwin experiment using a piezo device. Since a momentum dependent splitting behavior has been observed in other iron based superconductors, our observation confirms that the behavior is a universal one among iron based superconductors.