The 66th JSAP Spring Meeting, 2019

Presentation information

Oral presentation

10 Spintronics and Magnetics » 10.3 Spin devices, magnetic memories and storages

[11p-M101-15~21] 10.3 Spin devices, magnetic memories and storages

Mon. Mar 11, 2019 5:15 PM - 7:00 PM M101 (H101)

Kouta Kondou(RIKEN)

5:45 PM - 6:00 PM

[11p-M101-17] Spin-dependent diode performance in fully epitaxial magnetic tunnel junctions with bilayer tunnel barrier

Hidekazu Saito1, Shintaro Kon1,2, Sai Krishna Narayananellore3, Norihiro Matsuo1,2, Naoki Doko1,2, Yukiko Yasukawa2, Hiroshi Imamura1, Shinji Yuasa1 (1.AIST, 2.Chiba Inst. Tech., 3.NIMS)

Keywords:Magnetic tunnel junction, high frequency, energy harvesting

Metal/insulator/metal tunnel diodes have great potential for high-frequency rectifier systems, such as for THz/infrared detectors and energy harvesting applications. Amorphous or polycrystalline tunnel barriers have often been used in the tunnel diodes, and a single-crystalline tunnel barrier has never been used despite its high potential for tunnel-device applications. Here, we report on the spin-dependent diode properties of fully epitaxial Fe/ZnO/MgO/Fe(001) magnetic tunnel junctions (MTJs).
We found that the MTJs exhibited notable asymmetric I-V characteristics due to the bilayer tunnel barrier, and those diode properties strongly depended on the magnetization alignment of the Fe electrodes. The current responsibilities of the MTJs were largely enhanced at the anti-parallel alignment (2 ~ 3 A/W at RT) and almost comparable to those of high-performance MIIM diodes with dissimilar electrodes as well as to a state-of-the-art spin-torque diode. We demonstrated that a zero-bias anomaly in the tunnel conductance, which originates from the magnon excitations at the Fe/barrier interfaces, plays a crucial role in observed spin-dependent diode performance.