Non-isochronous exceptional point shift in coupled spin-torque nano-oscillators

This paper explores the nonlinear dynamics of mutually coupled spin-torque nano-oscillators and examines the relationship between non-isochronism and the appearance of exceptional points (EPs). We demonstrate that by manipulating the amplitudes of the driving force and the angles of the external bias magnetic field and spin-polarized current, it is possible to observe and fine-tune the position of EPs. Namely, EPs shift most significantly when the azimuth angle of the equilibrium state is approximately 90 degrees and the system's nonisochronism reaches its peak. The results of this investigation provide valuable insights for enhancing the performance of spintronic devices in applications such as microwave signal generation, spin-based computing, and sensing.