An unusually large enhancement of TMR at 77 K was observed in double barrier tunnel junctions (DBTJ). This is explained with extended Julliere's model which yields a twice larger TMR value. When the spin coherence length is much smaller at higher temperature, DBTJ is shown to work as a series of two single barrier tunnel junctions.
Bibliographical noteFunding Information:
This work was supported by the National Program for Tera-level Nanodevices of the Ministry of Science and Technology and the electron Spin Science Center at POSTECH established by KOSEF.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics