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arXiv · 2409.04112

An Explicit Wavefunction of the Interacting Non-Hermitian Spin-1/2 1D System

Yue Wang·Xiangyu Zhang·Zhesen Yang·Congjun Wu
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Abstract

We present an explicit Bethe-ansatz wavefunction to a 1D spin-$\frac{1}{2}$ interacting fermion system, manifesting a many-body resonance resulting from the interplay between interaction and non-Hermitian spin-orbit coupling. In the dilute limit, the Bethe-ansatz wavefunction is factorized into Slater determinants and a Jastrow factor. An effective thermodynamic distribution is constructed with an effective Hamiltonian including a repulsion resulting from Pauli's exclusion principle and a distinctive zigzag potential arising from the resonance. The competition between these effects leads to a transition from a uniformly distributed configuration to a phase separation. Clustering of particles with identical spins is observed in the latter phase, demonstrating that the many-body resonance effect is enhanced by the repulsive interaction.

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Yue Wang, Xiangyu Zhang, Zhesen Yang, Congjun Wu. 2024-09-06. An Explicit Wavefunction of the Interacting Non-Hermitian Spin-1/2 1D System. https://doi.org/10.1103/bhpz-17d2

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