Emergent Functional Interface Research Unit

Principal Investigator

PI Name

Masaki Nakano

Degree

Ph.D.

Title

Unit Leader

Brief Resume

2009	Ph. D., Tohoku University
2009	Postdoctoral Researcher, Institute for Materials Research, Tohoku University
2009	Postdoctoral Researcher, Department of Condensed Matter Physics, University of Geneva
2010	Postdoctoral Researcher, Correlated Electron Research Group, RIKEN
2012	Research Associate, Department of Advanced Materials Science, The University of Tokyo
2013	Research Associate, Institute for Materials Research, Tohoku University
2014	Project Lecturer, Quantum-Phase Electronics Center, School of Engineering, The University of Tokyo
2019	Project Associate Professor, Quantum-Phase Electronics Center, The University of Tokyo (-present)
2019	Unit Leader, Emergent Functional Interface Research Unit, RIKEN Center for Emergent Matter Science (-present)

Outline

We explore physical properties and functionalities emerging when materials are thinned down to monolayer limit. We in particular focus on monolayer properties of various 2D materials including hardly-cleavable and even metastable compounds that could be realized by employing non-equilibrium epitaxial growth technique, and develop novel device functionalities in combination with electric-field doping technique. In addition, we construct van der Waals superstructures by stacking different 2D materials aiming for discovery of novel quantum phases emerging at the interfaces.

Research Fields

Physics, Engineering, Chemistry, Materials Sciences

Keywords

TThin films and interfaces
Electric-field device
Strongly-correlated oxide
2D materials
Van der Waals epitaxy

Results

Emerging properties of van der Waals superstructures

When conducting electrons in a solid are confined within a two-dimensional plane, they behave differently from those moving freely in a three-dimensional space. This is called two-dimensional electron system, providing a unique platform in condensed matter physics research, although available only in semiconductor heterostructures or in electric-field devices in the 1980s and the 1990s. After entering the 21st century, however, the situation has been dramatically changed owing to the development of epitaxial growth technique as well as the discoveries of different types of materials as typified by graphene and topological insulators, and nowadays we can play with a variety of 2D phenomena more easily than in the past. We are in particular interested in emerging properties of 2D materials, and trying to build up functional interfaces from bottom-up approach by van der Waals epitaxy. We have already established a route to layer-by-layer epitaxial growth of various 2D materials, and now several research topics aiming for discovery of intriguing interface phenomena are in progress.

Van der Waals superstructures

Members

Masaki Nakano	Unit Leader	mnakano[at]riken.jp

Publications

Y. Wang, S. Kajihara, H. Matsuoka, B. K. Saika, K. Yamagami, Y. Takeda, H. Wadati, K. Ishizaka, Y. Iwasa, and M. Nakano

Layer-Number-Independent Two-Dimensional Ferromagnetism in Cr₃Te₄

Nano Lett. 22, 9964–9971 (2022)
H. Matsuoka, T. Habe, Y. Iwasa, M. Koshino, and M. Nakano

Spontaneous spin-valley polarization in NbSe₂ at a van der Waals interface

Nat. Commun. 13, 5129 (2022)
N. Yoshikawa, H. Suganuma, H. Matsuoka, Y. Tanaka, P. Hemme, M. Cazayous, Y. Gallais, M. Nakano, Y. Iwasa, and R. Shimano

Ultrafast switching to an insulating-like metastable state by amplitudon excitation of a charge density wave

Nat. Phys. 17, 909-914 (2021)
H. Matsuoka, S. E. Barnes, J. Ieda, S. Maekawa, M. S. Bahramy, B. K. Saika, Y. Takeda, H. Wadati, Y. Wang, S. Yoshida, K. Ishizaka, Y. Iwasa, and M. Nakano

Spin-orbit-induced Ising ferromagnetism at a van der Waals Interface

Nano Lett. 21, 1807 (2021)
M. Nakano, K. Shibuya, D. Okuyama, T. Hatano, S. Ono, M. Kawasaki, Y. Iwasa, and Y. Tokura

Collective bulk carrier delocalization driven by electrostatic surface charge accumulation

Nature 487, 459–462 (2012)