Materials Design Division

Advanced Chrystal Engineering Research Laboratory

Akira YOSHIKAWA

Prof.Akira YOSHIKAWA

  • Asso. Prof. Yuui YOKOTA
  • Assist. Prof. Takashi HANADA
  • Assist. Prof. Rikito MURAKAMI

Novel Functional Crystals and Advanced Sensors for Future

We develop novel functional crystals by vertically integrating upstream (material design) to downstream (device development) through interdisciplinary fusion and industry-academia collaboration. We not only synthesize single crystals, but also evaluate the response to external stimulation such as light, radiation, pressure, and heat, as well as piezoelectric properties using high-precision ultrasonic measurement technology. Based on the results, screening of crystal compositions is carried out in the immediate feedback form. When excellent properties are found, we fabricate high-quality bulk single crystals using the Czochralski method or Bridgeman method, which are suitable for mass production. We have developed several new scintillators, and have developed and commercialized radiation detectors and devices such as handy type radiation dose monitors, gamma-ray imaging cameras and PET for cancer diagnosis. We are also working on the development of infrared scintillation materials for decommissioning a nuclear reactor, development of difficult-to-process alloys for spark plugs and resistive heating wires for semiconductor deposition using shape-controlled solidification technology, and new single-crystal growth technology for functional oxides including wide band-gap semiconductors without using precious metals, in addition to the development of ultra-high melting point crystal growth technology.

scintillator crystal, wide band-gap semiconductors, piezoelectric single crystal, micro-pulling-down method, czochralski method, bridgeman method
(a) Ce doped GAGG crystals. (b) gamma camera with Ce:GAGG.

(a) Ce doped GAGG crystals
(b) gamma camera with Ce:GAGG

(a) Alloys with poor workability (b)High-temperature-tolerantLa-GPS crystal and its light yield property

(a) Ir-Rh type thermocouple.

(b) Resistance heating wire for OLED deposition cell

(c) Quick screening for candidate crystals using Micro-Pulling Down method (unique and original technology)

(a)Schematic image of OCCC method (b) Crystal growth in OCCC method (c) Synthesis of ultra-high temperature material by core heating method (d)halide eutectic scintillator

(a) Schematic image of OCCC method
(b) Crystal growth in OCCC method
(c) Synthesis of ultra-high temperature material by core heating method
(d) halide eutectic scintillator

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