OHTA Hiromichi

J-GLOBAL         Last updated: Aug 16, 2019 at 16:37
OHTA Hiromichi
Hokkaido University
Research Institute for Electronic Science
Job title
Dr. of Engineering(Tokyo Institute of Technology)
Research funding number
Google Analytics


I think that the approach for materials research could be divided into two main ways. One is a long-term diligent search for new substances, and the other is process development where a known substance is developed to be available as "a material." I have been closely watching the whole process of making furniture by my father, so that I seem to be better at process development in order to "make fine products." Firstly, I will fabricate high-quality thin films to know the intrinsic property which has been unable to be extracted from the data measured with dirty polycrystal such as ceramics or extremely small single crystal. My most interest in process development for now is to design electronic devices with the high-quality epitaxial thin films.

Research Areas


Academic & Professional Experience

Sep 2012
Professor, Hokkaido University, RIES
Oct 2003
Aug 2012
Associate Professor, Graduate School of Engineering, Nagoya University
Oct 2008
Mar 2012
 JST-PRESTO "Search for Nanomanufacturing Technology and Its Development" Researcher
Nov 1999
Sep 2004
 Hosono Transparent ElectroActive Materials Project, ERATO, JST
Jan 1998
Sep 2003
- Associate Professor, Graduate School of Engineering, Nagoya University
Apr 1996
Dec 1997
SANYO Electric Co.


Oct 1998
Sep 2001
Innovative and Engineered Materials, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology
Apr 1994
Mar 1996
Applied Chemistry, Graduate School of Engineering, Nagoya University
Apr 1990
Mar 1994
Applied Chemistry, Faculty of Engineering, Saitama University

Published Papers

Thermoelectric Phase Diagram of the SrTiO3 – LaTiO3 Solid-Solution System through a Metal to Mott Insulator Transition
Yuqiao Zhang*, Kenyu Sugo, Hai Jun Cho, and Hiromichi Ohta*
J. Appl. Phys.   126 075104   Aug 2019   [Refereed]
Electrical, optical and thermal transport properties of oxygen deficient amorphous WOx (2.5 < x < 3) films
Gowoon Kim, Hai Jun Cho*, Yu-Miin Sheu, and Hiromichi Ohta*
The Journal of Physical Chemistry C   123 15419   May 2019   [Refereed]
Room-temperature ferroelectric ferromagnet in 1D tetrahedral chain network
Kyeong Tae Kang, Chang Jae Roh, Jinyoung Lim, Taewon Min, Jun Han Lee, Kyoungjun Lee, Tae Yoon Lee, Seunghun Kang, Daehee Seol, Jiwoong Kim, Hiromichi Ohta, Amit Khare, Sungkyun Park, Yunseok Kim, Seung Chul Chae, Yoon Seok Oh, Jaekwang Lee, Jaejun Yu, Jong Seok Lee, and Woo Seok Choi*
Adv. Mater.   31 1808104   Apr 2019   [Refereed]
Buffer layer-less fabrication of high-mobility transparent oxide semiconductor, La-doped BaSnO3
Anup Sanchela*, Mian Wei, Joonhyuk Lee, Gowoon Kim, Hyoungjeen Jeen, Bin Feng, Yuichi Ikuhara, Hai Jun Cho, Hiromichi Ohta*
Journal of Materials Chemistry C   7 5797-5802   Apr 2019   [Refereed]
Electron sandwich doubles the thermoelectric power factor of SrTiO3
Yuqiao Zhang and Hiromichi Ohta
Phys. Status Solidi A   1800832   Mar 2019   [Refereed][Invited]
Thermal conductivity tensor of NbO2
Hai Jun Cho*, Gowoon Kim, Takaki Onozato, Hyoungjeen Jeen, and Hiromichi Ohta
International Journal of Heat and Mass Transfer   137 263   Mar 2019   [Refereed]
Peculiar magnetotransport properties in La0.67Sr0.33MnO3/LaAlO3/SrTiO3
Michihiko Yamanouchi*, Tatsuro Oyamada, and Hiromichi Ohta
AIP Advances   9 035129   Mar 2019   [Refereed]
Current-induced modulation of coercive field in the ferromagnetic oxide SrRuO3
Michihiko Yamanouchi*, Tatsuro Oyamada, Koichi Sato, Hiromichi Ohta, and Jun’ichi Ieda
IEEE Transactions on Magnetics   1400604   Feb 2019   [Refereed]
Fast operation of a WO3-based solid-state electrochromic transistor
Takaki Onozato, Yukio Nezu, Hai Jun Cho, and Hiromichi Ohta*
AIP Advances   9 025122   Feb 2019   [Refereed]
Formation of environmentally stable hole-doped graphene films: Instantaneous and high-density carrier doping by a boron-based oxidant
Kaito Kanahashi, Naoki Tanaka, Yoshiaki Shoji, Mina Maruyama, Il Jeon, Kenji Kawahara, Masatou Ishihara, Masataka Hasegawa, Hiromichi Ohta, Hiroki Ago, Yutaka Matsuo, Susumu Okada, Takanori Fukushima, and Taishi Takenobu*
npj 2D Materials and Applications   3 7   Feb 2019   [Refereed]
Thermopower modulation clarification of the operating mechanism in wide bandgap BaSnO3−SrSnO3 solid-solution based thin film transistors
Anup V. Sanchela*, Mian Wei, Hai Jun Cho, and Hiromichi Ohta*
Small   15 1805394   Jan 2019   [Refereed]
Effects of vacuum annealing on the electron mobility of epitaxial La-doped BaSnO3 films
Hai Jun Cho*, Takaki Onozato, Mian Wei, Anup Sanchela, and Hiromichi Ohta*
APL Mater.   7 022507   Dec 2018   [Refereed]
Extremely light carrier effective mass in a distorted simple metal oxide
Gowoon Kim, Yu-Qiao Zhang, Taewon Min, Hoyoung Suh, Jae Hyuck Jang, Hyeonjun Kong, Joonhyuk Lee, Jaekwang Lee, Tae-Yeol Jeon, Inwon Lee, Jinhyung Cho, Hiromichi Ohta* and Hyoungjeen Jeen*
Adv. Electron. Mater.   5 1800504   Dec 2018   [Refereed]
Oxygen vacancies allow tuning the work function of vanadium dioxide
Rongbin Wang, Takayoshi Katase, Ke-Ke Fu, Tianshu Zhai, Jiacheng Yang, Qiankun Wang, Hiromichi Ohta, Norbert Koch, and Steffen Duhm
Adv. Mater. Interfaces      Oct 2018   [Refereed]
Crystallographic orientation – surface energy – wetting property relationships of rare earth oxides
Jason Tam, Bin Feng, Yuichi Ikuhara, Hiromichi Ohta*, Uwe Erb*
J. Mater. Chem. A      Sep 2018   [Refereed]
Double thermoelectric power factor of a 2D electron system
Yuqiao Zhang, Bin Feng, Hiroyuki Hayashi, Cheng-Ping Chang, Yu-Miin Sheu, Isao Tanaka, Yuichi Ikuhara, and Hiromichi Ohta
Nature Communications   9 2224   Jul 2018   [Refereed]
Large thickness dependence of the carrier mobility in a transparent oxide semiconductor, La-doped BaSnO3
Anup V. Sanchela*, Mian Wei, Haruki Zensyo, Bin Feng, Joonhyuk Lee, Gowoon Kim, Hyoungjeen Jeen, Yuichi Ikuhara, and Hiromichi Ohta*
Appl. Phys. Lett.   112 232102   Jun 2018   [Refereed]
Plasmon-Assisted Polarity Switching of a Photoelectric Conversion Device by UV and Visible Light Irradiation
Keisuke Nakamura, Tomoya Oshikiri, Kosei Ueno, Takayoshi Katase, Hiromichi Ohta, and Hiroaki Misawa
J. Phys. Chem. C   122(25) 14064-14071   Apr 2018   [Refereed]
Stoichiometric and oxygen deficient VO2 as versatile hole injection electrode for organic semiconductors
Ke-Ke Fu, Rong-Bin Wang, Takayoshi Katase, Hiromichi Ohta, Norbert Koch, and Steffen Duhm
ACS Appl. Mater. Interfaces   10 10552-10559   Mar 2018   [Refereed]
Chemical hole doping into large-area transition metal dichalcogenide monolayers using boron-based oxidant
Hirofumi Matsuoka, Kaito Kanahashi, Naoki Tanaka, Yoshiaki Shoji, Lain-Jong Li, Jiang Pu, Hiroshi Ito, Hiromichi Ohta, Takanori Fukushima, and Taishi Takenobu
Jpn. J. Appl. Phys.   57 02CCB15   Jan 2018   [Refereed]

Books etc

10.Fabrication, characterization, and modulation of functional nanolayers, Nanoinformatics
Hiromichi Ohta and Hidenori Hiramatsu (Part:Joint Work, 10.Fabrication, characterization, and modulation of functional nanolayers)
Springer   Feb 2018   
Metal Oxide-Based Thin Film Structures (1st Edition) Formation, Characterization and Application of Interface-based Phenomena
OHTA Hiromichi (Part:Joint Work, Chapter 4.3 Thermoelectrics)
ELSEVIER   Sep 2017   
Multifunctional Oxide Heterostructures(Eds.) E. Y. Tsymbal, E. R. A. Dagotto, C-B. Eom, and R. Ramesh
H. Ohta and K. Koumoto (Part:Joint Work, Chapter 10 Thermoelectric oxides: films and heterostructures)
Oxford   2012   
Handbook of Transparent Conductors (Editors: David Ginley, Hideo Hosono, and David Paine)
Hiromichi Ohta (Part:Joint Work, Chapter 14 Junctions)
Springer   2010   
Handbook of Transparent Conductors (Editors: David Ginley, Hideo Hosono, and David Paine), Chapter 14 Junctions
Springer   2010   

Conference Activities & Talks

Double enhancement of thermoelectric power factor in SrTiO3 based electron sandwitch [Invited]
Hiromichi Ohta, Yuqiao Zhang
4th Functional Oxide Thin Films for Advanced Energy and Information Technology Conference   17 Jul 2019   
Thermoelectric properties of two-dimensional electron system -superlattices and TFT channel- [Invited]
OHTA Hiromichi
2019 Asia-Pacific Workshop on Fundamentals and Applications of Advanced Semiconductor Devices (AWAD 2019)   1 Jul 2019   
Electron transport properties of transparent oxide semiconductor, BaSnO3-SrSnO3: Epitaxial films and thin film transistors [Invited]
Hiromichi Ohta, Anup V. Sanchela
EM-NANO 2019   19 Jun 2019   
Electric field thermopower modulation measurements of two-dimensional electron gas [Invited]
OHTA Hiromichi
International mini-workshop on Nonequlibrium transport and phase transition in novel materials   26 Nov 2018   
Double thermoelectric powerfactor of a 2D electron system [Invited]
OHTA Hiromichi
the International Conference on Electronic Materials and Nanotechnology for Green Environment (ENGE 2018)   11 Nov 2018   
Development of three-terminal electrochromic device using water electrolysis [Invited]
OHTA Hiromichi
IUMRS-ICEM 2018   19 Aug 2018   
Thermopower of 2D electron systems [Invited]
OHTA Hiromichi
The 2018 International Symposium for Advanced Materials Research (ISAMR 2018)   16 Aug 2018   
Double enhancement of thermoelectric power factor in two-dimensional electron system [Invited]
OHTA Hiromichi
the 16th International Nanotech Symposium & Nano-Convergence Exhibition, NANO KOREA 2018   10 Jul 2018   
Electric field thermopower modulation of two-dimensional electron gas [Invited]
OHTA Hiromichi
The 25th International Workshop on Active-Matrix Flatpanel Displays and Devices – TFT Technologies and FPD Materials – (AM-FPD 18)   3 Jul 2018   
Thermoelectric Seebeck effect of 2D electron systems [Invited]
OHTA Hiromichi
The first International Joint Symposium of CEFMS-NCTU, RCAS-AS (Taiwan) and 5-Star Alliance (Japan)   18 May 2018   


2010 - 2012


Thermoelectric Material, Infared Sensor and Image Forming Device
WO 2007/132782 A1
Thermoelectric Conversion Material and Production Method for Thermoelectric Conversion Material
WO 2006/054550 A1
Thermoelectric Material, Infared Sensor and Image Forming Device
(PCT) WO 2007/132782 A1