Researcher Database

（Last updated : 2025-03-17 15:19:16）　

KOREEDA AKITOSHI

Department / Course College of Science and Engineering Department of Physical Sciences

Title / Position Professor

Other Affiliations
1.	College of Science and Engineering Department of Physical Sciences
2.	Graduate School of Science and Engineering

Academic background
1.	2000/03 Degree Acquisition	│ Tohoku University Ph. D
2.	～1995/03	Department of Physics 2 │ Faculty of Science │ Tohoku University │ Graduated
3.	～1998/03	Doctoral Program (1st Semester) │ Department of Physics │ Graduate School of Science │ Tohoku University │ Completed
4.	～2000/03	Doctoral Program (2nd Semester) │ Department of Physics │ Graduate School of Science │ Tohoku University │ Completed

Business career
1.	2015/04/01	Professor │ College of Science and Engineering │ Ritsumeikan University
2.	2013/04/01 ～ 2015/03/31	Associate Professor │ College of Science and Engineering │ Ritsumeikan University
3.	2010/10/01 ～ 2014/03/31	PRESTO Researcher │ │ JST
4.	2004/04/01 ～ 2005/03/31	│ Center of for the Advancement of Higher Education │
5.	2001/04/01 ～ 2013/03/31	Assistant Professor │ Graduate School of Science │ Tohoku University
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Committee and society
1.	2018/09/01 ～	Japan-Korea Conference on Ferroelectricity Chairman

Research activities
1.	1995 ～	Physical Society of Japan
2.	2010 ～ 2018	The Laser Society of Japan
3.	2009 ～ 2018	The Materials Research Society of Japan

Subject of research
1.	Optical generation and wave control of heat eigenstates
2.	Understanding of fractal dynamics in relaxor ferroelectrics

Research summary
[Acquire minute information of energy, lifespan, etc., of various states of excitation inside matters by high-accuracy spectrometry fully utilizing lasers, and challenge the various unsolved problems in condensed matter physics] Various probes and measurement methods are used in experimental studies in condensed matter physics. Of these, laser spectrometry has realized very high frequency accuracy (= light that maintains vibration for a long period) and very short pulse (= light that only spark for an instant) and can be said to be a dynamic experimental method that is able to search from “eternity to a moment”. On the other hand, spatially, the wavelength of light is far longer than unit of matter construction but far shorter than the macro natured size of the test material. This being the case, it is positioned as a method to search the physical properties of intermediate scale matters, that cannot be covered by a macro natured measurement such as crystal structure analysis and attaching electrodes. In our laboratory, through high-precision spectrometry fully utilizing lasers, minute information on energy and lifespan under various states of excitation inside matters are acquired, in the challenge to solve various problems that have not been solved. Furthermore, exceeding only “observing”, we will be seeking the possibility of creating a special excited state inside matter using laser light and to freely control the excited state. Control of matter states by light will prove to be an important foundation that will lead to diverse future applications in energy transportation, communications, etc. \ Major issues of research to be conducted from FY2013 onwards contain the following: Create and control temperature (entropy) wave motion by laser. Ultra-high precision laser spectrometry of ultra-sonic waves (phonon) and spin waves (magnon) Understand the properties of regular crystal that indicate massive response using the concept of complex systems. Spectrometric study on ultra-low temperature properties of matters with irregular structure (glass morphogenic substance) Observation of ultra-high speed relaxation of excited states by ultra-high speed spectrometry using ultra-short pulse lasers. Establish a new ultra-high precision/ultra-high speed laser spectrometry system , and others The substances used as subjects for the research include “ferroelectric” related substances that are materials for nonvolatile memories and ultra-small capacitors, “glass morphogenic substances” that do not have a regular structure like crystals, “ferromagnetic” related substances that are materials for magnetic memories, “multiferroic substances” that show properties of both ferroelectric and ferromagnetic substances, “spintronic substance” where spin waves are responsible for energy transportation, “quantum solids and quantum liquids” where quantum fluctuation induce special properties, (especially condensed hydrogen liquid), and others. These substance groups display various new properties that cannot be explained by conventional common sense, and an even more precise measurement and a new physics point of view is desired to understand their nature.

Present specialized field
Applied materials, Condensed matter physics I, Condensed matter physics II (Keyword：laser spectroscopy, light scattering, Brillouin scattering, Rayleigh scattering, ferroelectrics, quantum paraelectrics, relaxors, quantum solids, quantum liquids)

Papers
1.	2017/09	Excitation of coupled spin-orbit dynamics in cobalt oxide by femtosecond laser pulses │ Nature Communications │ 8 (1),pp.638
2.	2017/05	Formation of metallic cation-oxygen network for anomalous thermal expansion coefficients in binary phosphate glass │ Nature Communications │ 8,pp.15449
3.	2012/11/05	Fractal Dynamics in a Single Crystal of a Relaxor Ferroelectric │ Physical Review Letters │ 109,pp.197601(1-5)
4.	2009/10/02	Light scattering in a phonon gas │ Physical Review B │ 80 (16),pp.165104(1-25)
5.	2007/12/28	Second Sound in SrTiO3 │ Physical Review Letters │ 99 (26),pp.265502(1-4)
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Academic conference presentation
1.	2018/09/09	Boson Peak and Fracton of Sodium Carboxymethyl Starch Detected by Terahertz Time-Domain and Low-Frequency Raman Spectroscopies
2.	2018/09/09	Boson Peak Detection of Colored Craft Glass by Terahertz Time-Domain Spectroscopy
3.	2018/09/09	Detection of Boson Peak and Fractal Dynamics of Protein by Terahertz Time-Domain Spectroscopy
4.	2018/09/09	Terahertz Time-Domain Spectroscopy and Low-Frequency Raman Scattering of Boson Peak Dynamics of Lithium Borate Glasses
5.	2018/09/09	Terahertz Time-Domain Spectroscopy of Protein Myoglobin: Detection of Boson Peak and Fracton
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Grants-in-Aid for Scientific Research -KAKENHI-
1.	2009/04 ～ 2011/03	Generation and control of coherent second sound in quantum paraelectrics

Competitive grants, etc. (exc. KAKENHI)
1.	2010/10 ～ 2014/03	Optical generation and wave control of heat eigenstates │ Research by External Competitive Fund │ Japan Science and Technology Agency, PRESTO