Transient to steady state current in a magnetic tunnel junction

Sung Po Chao^1*, Narasimha Raju Chebrolu^1,2

¹Physics, National Kaohsiung Normal University, Kaohsiung, Taiwan
²Physics, seoul university, Seoul, Korea

* Presenter:Sung Po Chao, email:spchao@gmail.com

We study the transient dynamics of the magnetic tunnel junction formed by the ferromagnetic leads and an insulating barrier (or quantum dot) sandwiched in between. Magnetic fluctuations in the central barrier or dot region is modeled as magnons, which could be influenced by the external magnetic field and the electronic states within it. At finite temperature, phonons from this central region could also modify the transient current. We model these effects by using spinful Anderson-Holstein model and compute transient current perturbatively using Keldysh Green’s function. Different relaxation time to steady state is shown for different physical measurable quantities, which could be useful for device makings with multiple on-off time scales within one device.

Keywords: magnetic tunnel junction, magnon