In this Letter, we study the conditions under which on-site dissipations can induce non-Hermitian skin modes in non-Hermitian systems. When the original Hermitian Hamiltonian has spinless time-reversal symmetry, it is impossible to have skin modes; on the other hand, if the Hermitian Hamiltonian has spinful time-reversal symmetry, skin modes can be induced by on-site dissipations under certain circumstances. As a concrete example, we employ the Rice-Mele model to illustrate our results. Furthermore, we predict that the skin modes can be detected by the chiral tunneling effect; that is, the tunneling favors the direction where the skin modes are localized. Our Letter reveals a no-go theorem for the emergence of skin modes and paves the way for searching for quantum systems with skin modes and studying their novel physical responses.

• Received 7 March 2020
• Accepted 21 September 2020

DOI:https://doi.org/10.1103/PhysRevLett.125.186802