Non-Hermitian dimerized interacting Kitaev chain: Exact and numerical solutions

Non-Hermitian models have risen as a new paradigm to manipulate and interpret various emergent quantum phenomena. While numerous studies have been focused on exploring (effective) non-Hermitian non-interacting models. The role of interactions in modifying the non-interacting non-Hermitian physics still needs to be well-explored. In this talk, I will present how incorporating many-body interactions can enrich the non-interacting physics. To be more precise, combining our exact analytical results and numerical calculations, I will discuss the phase diagram of the non-Hermitian dimerized interacting Kitaev chain. Here, the non-Hermiticty is due to the complex-valued nearest-neighbor density-density interaction strength. I will show that the ground state degeneracy of this system may be fourfold, twofold, or nondegenerate depending on the parameter regimes. I will further discuss how these degeneracies are lifted in the presence of non-Hermiticity. Elaborating on this behavior clarifies the role of non-Hermiticity in washing out multiple phases in the phase diagram of the Hermitian interacting model.