Heisenberg spin-1/2 XXZ chain in the presence of electric and magnetic fields

作者:Thakur Pradeep*; Durganandini P
来源:PHYSICAL REVIEW B, 2018, 97(6): 064413.
DOI:10.1103/PhysRevB.97.064413

摘要

We study the interplay of electric and magnetic order in the one-dimensional Heisenberg spin-1/2 XXZ chain with large Ising anisotropy in the presence of the Dzyaloshinskii-Moriya (DM) interaction and with longitudinal and transverse magnetic fields, interpreting the DM interaction as a coupling between the local electric polarization and an external electric field. We obtain the ground state phase diagram using the density matrix renormalization group method and compute various ground state quantities like the magnetization, staggered magnetization, electric polarization and spin correlation functions, etc. In the presence of both longitudinal and transverse magnetic fields, there are three different phases corresponding to a gapped Neel phase with antiferromagnetic (AF) order, gapped saturated phase, and a critical incommensurate gapless phase. The external electric field modifies the phase boundaries but does not lead to any new phases. Both external magnetic fields and electric fields can be used to tune between the phases. We also show that the transverse magnetic field induces a vector chiral order in the Neel phase (even in the absence of an electric field) which can be interpreted as an electric polarization in a direction parallel to the AF order.

  • 出版日期2018-2-20