Introduction of Ohta Laboratory

Our goal is to investigate how dynamics induced by photoirradiation in molecules and molecular assemblies is influenced by application of electric field and/or magnetic field, how molecular configuration and electronic structure accompanied by photoexcitation change, and how photoinduced conductivity, electrical and magnetic characteristics such as expression of electroluminescence, and photoelectric conversion characteristics are related with optical characteristics.

Based on these results, we will clarify how “photoexcitation dynamics,” “structure of photoexcited molecule,” and “optical functional property” are related to one another, and aim to freely control various reactions.

In addition, we are searching expression of new functional property associated with light such as “photoinduced superconductivity.” It is indicated that a strong electric field that cannot be obtained in a general laboratory system exists in an organism. We are examining the relation of the organism with intracellular dynamics and with vital function by fluorescence lifetime imaging microscopy (FLIM) while focusing on the environment in the cell, in particular, the existence of an intracellular electric field and its distribution.

Main Subjects of Research

  • Control of structure and dynamics by light, electric field, and magnetic field
  • Generation of new optical functional property
  • Creation of photoinduced superconductivity
  • Study on intracellular electric field and function by fluorescence lifetime imaging microscopy

Keywords of Research

Interaction between light and materials, Eelectric field effect, Magnetic field effect, Electrical conductivity, Optical control of functional property, Photoinduced superconductivity, Optical control of ionic conductivity, Electroluminescence (EL) element, Organic solar cell, Electric field in the body, Intracellular environment, Fluorescence lifetime imaging microscopy (FLIM)


  • March 31, 2015
    Prof. Ohta retired Hokkaido University (he will continue his research at National Chiao Tung University in Taiwan, and the communication with him is possible with the same e-mail address)
  • March 31, 2015
    “Laboratory of Molecular Photonics” is closed.
  • March 31, 2015
    Dr. Awasthi retired Hokkaido Univesity (he will work at National Chiao Tung University in Taiwan from April, 2015)
  • March 31, 2015
    Dr. Sabeth retired Hokkaido University, and she went back to Bangladesh together with her husband (Dr. Md. Serajul Islam)
  • March 26, 2015
    It was approved that Prof. Ohta becomes Prof. Emeritus at Hokkaido University after his retirement.
  • March 25, 2015
    Mr. K. Okoshi and Mr. T. Mukai finished a master course of Graduate School of Environmental Science and received a Master Degree of Environmental Science at Hokkaido University.
  • March 16, 2015
    Prof. Ohta gave “the Last Lecture” before his retirement at Research Institute for Electronic Science at Hokkaido University.
  • Septembet 21, 2014
    Prof. Ohta received “The Japan Society of Molecular Science Award”, which was introduced in the homepage of the Japan Society of Molecular Science as a “NEWS”.
  • May 26, 2014
    Prof. Ohta received “The Spectroscopical Society of Japan Award” and gave the Award Lecture at Riken, which was introduced by the society journal “Bunko Kenkyu” (Vol. 64, No. 4, 140 (2014)).
  • May 1, 2014
    Associate Professor T. Nakabayashi promoted to full Professor at Graduate School of Pharmaceutical Science of Tohoku University in Sendai.
  • May 1, 2014
    Drs. Farazana Sabeth and Md. Serajul Islam joined the Laboratory as postdoctoral fellow and visiting researcher, respectively.
  • April 1, 2014
    Mrs. Kikuchi was employed as a secretary of the Laboratory.
  • March 31, 2014
    Mrs. Nakaoka quited the secretary position of the laboratory to concentrate on the secretary position of another Laboratory at the same Institute.
  • February 17, 2014
    Review article of the “effects of photoirradiation and application of electric field on electrical conductivity” was reported as a Feature Article of the Journal of Physical Chemistry, along with the cover figure of the journal.
  • September 25, 2013
    On September 25, 2013, Hung-Chu Chiang took a doctorate degree of Hokkaido University (Doctor of Philosophy in environmental science). Title of doctorate is “Study on Electroabsorption and Electrophotoluminescence of Optoelectronic Functional Materials in Solution.”
  • September 1, 2013
    A letter “Ideas Associated with Institute for Molecular Science” contributed by Professor Ohta is posted in “IMS Letters” (vol. 68) issued on September 1, 2013.
  • August 19, 2013
    A preface “Emotion and Impression” contributed by Professor Ohta is posted in “PHOTOCHEMISTRY” (vol.44-2), a bulletin of the Japanese Photochemistry Association, issued on August 19, 2013.
  • April 1, 2013
    On April 1, 2013, Ms. Nakaoka is adopted as a secretary.
  • April 1, 2013
    On April 1, 2013, Doctor Kamlesh Awasthi is adopted as a specially appointed assistant professor.
  • April 1, 2013
    On April 1, 2013, Professor Ohta becomes a specially appointed professor.
  • April 1, 2013
    On April 1, 2013, Dr. Iimori promoted to the associate professor at Muroran Institute of Technology.
  • March 31, 2013
    On March 31, 2013, Ms. Hashimoto resigned as a secretary.
  • March 25, 2013
    In March, 2013, Kaname Oinuma finished master’s course (major in Hokkaido University, Graduate School of Environmental Science, Division of Environmental Materials Science). Title of master’s thesis is "Time-resolved measurement of changes in electrical conductivity of molecular conductor λ-(BETS)2FeCl4 exhibiting metal-insulator transition by photoexcitation."
  • March 5, 2013
    On March 5, 2013, Hung-Chu Chiang, the third year of the doctoral program, was awarded to a best poster award in Taiwan-Japan Workshop on Nano Devices 2013. The title of lecture is "Application of Stark Spectroscopy in Absorption and Photoluminescence to Optoelectronic Functional Materials."
  • November 5, 2012
    On November 5, 2012, professor Ohta is introduced in Like! Hokudai Facebook under the title of "Apoptosis to cells with an epoch-making method."
  • September 27, 2012
    On September 27, 2012, "Control of intracellular function by nanosecond pulse electrical field: Observation of apoptosis induction is successful using fluorescence lifetime imaging" is issued through press release and introduced in Hokkaido Medical Newspapers dated October 19.
  • September 13, 2012
    On September 13, 2012, Assistant Professor Iimori was awarded to a prize for encouragement of the Japanese photochemistry Association under the title of "Control of electrical physical properties of molecular crystal by light and electric field."
  • September 13, 2012
    On September 13, 2012, Professor Ohta was awarded to a special lecturer of photochemistry discussion session under the title of “Photochemistry and electric field effect."
  • April 26, 2012
    On April 26, "Free control of transition between organic material insulator and metal is successful through synergetic effect of electric field and light" is issued through press release and introduced in the Science News ltd. on May 18.
  • November 2011
    In November 2011, Professor Ohta is appointed as a member of International Steering Committee of the Third Asian Spectroscopy Conference.
  • September 7, 2011
    On August 23, "Measurement of pH in a single cell by autofluorescence" is issued through press release and introduced in the Nikkan Kogyo Shimbun on September 7.
  • September 2, 2011
    On August 23, "Measurement of pH in a single cell by autofluorescence" is issued through press release and introduced in the Science News ltd. on September 2.
  • October 7, 2011
    Conference presentation, etc. are updated.
  • October 7, 2011
    Contents of research are updated.
  • August 19, 2011
    When in need of materials for Ohta laboratory, please inform us by e-mail.
  • August 19, 2011
    Website is updated

N20W10, Kita-Ward Sapporo 001-0020 JAPAN
Laboratory of Molecular Photonics,
Section of Material and Molecular Sciences,
Research Institute for Electronic Science (RIES)

Graduate School of Environmental Sceince,
Hokkaido University


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