Low-Frequency Electronic Noise and Charge Transport Dynamics in Electrically Tunable Magnetic Tunnel Junctions
Jhen-Yong Hong (洪振湧)1*, Chen-Feng Hung2, Dah-Chin Ling1, Isidoro Martinez3, Farkhad G. Aliev3, Minn-Tsong Lin2,4,5
1Department of Physics, Tamkang University, New Taipei City 25137, Taiwan
2Department of Physics, National Taiwan University, Taipei 10617, Taiwan
3Depto Fisica de la Materia Condensada, Universidad Autonoma de Madrid, Madrid 28049, Spain
4Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
5Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan
* Presenter:Jhen-Yong Hong (洪振湧)
Electrical control of charge and magneto- transport properties of magnetic tunnel junctions (MTJs) have recently paid the way towards the development of new spintronic devices through a combination of resistive switching (e.g. “memristance”) and tunneling magnetoresistance, which is promising for practical applications in multibit non-volatile data storage and artificial neuronal computing. Here, magneto-transport properties, I-V characteristics, and low-frequency noise spectroscopy of AlOx MTJs are experimentally investigated, demonstrating that both 1/f noise and random-telegraph noise (RTN) are important factors responsible for the performance and application of non-volatile devices. The measured 1/f noise can be explained by an empirical formulation of mobility fluctuations with a substantial change in the Hooge’s parameter as the MTJs are tuned from the high resistance to the low resistance states. The findings could be associated with the (re)distribution and the (re)migration of oxygen ions and oxygen vacancies in the barrier, suggesting that conductivity dynamics plays an important role in the control of electron tunneling through AlOx barriers.

This work is financially supported by Ministry of Science and Technology, Taiwan (MOST 106-2112-M-032-001 and MOST 106-2119-M-002-040).

Keywords: Resistive Switching, Magnetic Tunnel Junction (MTJ), Magnetoresistance (MR), 1/f Noise, Random-Telegraph Noise (RTN)