Strong Correlation Interface Research Group

Principal Investigator

PI Name Masashi Kawasaki
Degree D.Eng.
Title Group Director
Brief Resume
1989D.Eng., University of Tokyo
1989Postdoctoral Fellow, Japan Society for the Promotion of Science
1989Postdoctoral Fellow, T. J. Watson Research Center, IBM, USA
1991Research Associate, Tokyo Institute of Technology
1997Associate Professor, Tokyo Institute of Technology
2001Professor, Tohoku University
2007Team Leader, Functional Superstructure Team, RIKEN
2010Team Leader, Strong-Correlation Interfacial Device Research Team, RIKEN
2011Professor, University of Tokyo
2013Deputy Director, RIKEN Center for Emergent Matter Science (CEMS) (-present)
2013Group Director, Strong Correlation Interface Research Group, Strong Correlation Physics Division, RIKEN CEMS (-present)

Outline

Artificial interfaces and superlattices are designed and constructed with the aid of cutting-edge thin film technology of transition-metal oxides having various ordered structures in charge, spin and orbital degrees of freedom of electrons. The responses of these superstructures to such stimuli as magnetic field, electrical field and photo irradiation are examined to elucidate cross-correlated functionalities. These studies will enable us to create new kinds of devices such as switches, memories, photovoltaics and sensors to explore a novel concept of correlated quantum electronics.

Research Fields

Physics, Engineering, Chemistry, Materials Sciences

Keywords

Oxides
Thin films and interfaces
Quantum devices
Magnetoelectric effect
Photovoltaic effect

Results

Control of skyrmions by utilizing oxide interfaces

Electron transport coupled with magnetism has attracted attention over the years. Among them, recently discovered is topological Hall effect (THE), originating from scalar spin chirality, that is, the solid angle subtended by the spins. THE is found to be a promising tool for probing the Dzyaloshinskii-Moriya (DM) interaction and consequent magnetic skyrmions. This interaction arises from broken inversion symmetry and hence can be artificially introduced at interface; this concept is lately verified in metal multilayers. However, there are few attempts to investigate such DM interaction at interface through electron transport. We clarified how the transport properties couple with interface DM interaction by fabricating the epitaxial oxide interface. We observed THE in epitaxial bilayers consisting of ferromagnetic SrRuO3 and paramagnetic SrIrO3 over a wide region of both temperature and magnetic field. The magnitude of THE rapidly decreases with the thickness of SrRuO3, suggesting that the interface DM interaction plays a significant role. Such interaction is expected to realize a 10-nm-sized Néel-type magnetic skyrmion. The present results established that the high-quality oxide interface enables us to tune the effective DM interaction; this can be a step toward future topological electronics.

Schematic of skyrmion generation at oxide interfaces

Members

Masashi Kawasaki

Group Director m.kawasaki[at]riken.jp R
Jobu Matsuno Senior Research Scientist matsuno[at]riken.jp R
Kei Takahashi Senior Research Scientist kei.takahashi[at]riken.jp R

Masao Nakamura

Senior Research Scientist masao.nakamura[at]riken.jp R

Denis Maryenko

Research Scientist maryenko[at]riken.jp

Yusaburo Segawa

Research Consultant

Articles

お問い合わせ

  

TEL:+81-(0)48-467-9604

E-mail:
m.kawasaki[at]riken.jp

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