Low frequency noise and magnetization fluctuation in AlOX magnetic tunnel junctions
Jhen-Yong Hong1*, Chun-Yen Chen1,2, Yu-Hui Tang2, Dah-Chin Ling1, Minn-Tsong Lin3, Cesar Gonzalez-Ruano4, Farkhad G. Aliev4
1Department of Physics, Tamkang University, New Taipei City, Taiwan
2Department of Physics, National Central University, Taoyuan, Taiwan
3Department of Physics, National Taiwan University, Taipei city, Taiwan
4Department of Condensed Matter Physics, Universidad Autónoma de Madrid, Madrid, Spain
* Presenter:Jhen-Yong Hong, email:jyhong@mail.tku.edu.tw
Low-frequency magneto-resistive noise in AlOx magnetic tunnel junctions (MTJs) was studied at room temperature. The measured 1/f noise and the frequency-dependent Fano factor around the magnetic configuration reversal indicates that the magnetization fluctuation would be the main origin of the 1/f magnetic noise. Interestingly, random telegraph noise (RTN) was observed for both bare MTJs and MTJs with RS characteristics during the transition of magnetization switching. A comparison of the analysis with 1/f noise and magneto-resistive curve as a function of the magnetic field shows that the changes in magnetization dynamics are reflected in the RTN. The results suggest that the voltage-driven oxygen ions in the AlOx barrier could influence the interaction of transmission electrons from two relative magnetizations.

Keywords: Magnetic tunnel junctions (MTJs), Low-frequency noise (LFN), Random telegraph noise (RTN)