HOME > Profile > SHIMAMURA, Kiyoshi
- Address
- 305-0044 1-1 Namiki Tsukuba Ibaraki JAPAN [Access]
Accepting Students
Research
- Keywords
結晶成長、結晶材料科学、光応用
PublicationsNIMS affiliated publications since 2004.
Published patent applications
- 酸化物結晶、その製造方法、および、その用途 (2026)
- 酸化物結晶、その製造方法、それを用いたシンチレータ材料、および、その用途 (2026)
- 酸化物結晶、その製造方法、および、その用途 (2026)
Society memberships
日本結晶成長学会, 応用物理学会, 日本材料科学会, American Ceramic Society, 日本電子材料技術協会
Research Center for Electronic and Optical Materials
novel functional single-crystal materials
single crystal, crystal growth, optical applications, piezoelectric materials, semiconductors
Overview
Research is being carried out on the design and bulk single crystallization of new single-crystal materials, as well as their evaluation and device development. Optical single crystals—including laser, nonlinear optical, magneto-optical, and scintillator crystals—are the central focus, alongside bulk single crystals for next-generation applications such as wide bandgap semiconductors, piezoelectric, and ferroelectric materials. Various material systems, ranging from oxides to halides and nitrides, are being explored, and crystal growth techniques appropriate for each are being developed. Collaboration with universities, research institutes, and companies is actively pursued, together with international exchanges, with the aim of conducting wide-ranging research—from basic studies to practical applications—from new perspectives.
Novelty and originality
● Bulk single-crystal growth of materials with ultra-high melting points
● Bulk single-crystal growth of halides, with a focus on fluorides
● Design of functional single-crystal materials with properties surpassing conventional characteristics
● A wide range of investigations, from optical to piezoelectric and semiconductor materials
● Development of novel crystal growth techniques, such as bulk single-crystal growth by hydrothermal synthesis
Details
● (Left) 2-inch diameter core-free Y₃Al₅O₁₂ (YAG) single crystal. This single crystal, which is coreless and highly homogeneous, is useful for high-power lasers and lenses.
● (Upper right) 3-inch diameter Tm,Ho:LiYF₄ single crystal. Useful for eye-safe lasers.
● (Lower right) Ca₃TaAl₃Si₂O₁₄ (CTAS) single crystal operates as a piezoelectric material at high temperatures. It exhibits a high resistivity of 10¹¹ Ω·cm at 400°C, which is higher than LTGA.
Single-crystal phosphors for ultra-high brightness white lighting using blue LEDs. (Left) Ce:Y₃Al₅O₁₂ (YAG), (Right) Ce:Lu₃Al₅O₁₂ (LuAG) single-crystal phosphors. Compared to conventional ceramic powder phosphors, these exhibit higher internal quantum efficiency that is maintained even at high temperatures, and resist temperature increases even under strong blue irradiation. As a result, the luminous intensity of white LEDs is overwhelmingly higher than that of conventional products.
Summary
Materials exhibiting superior properties compared to conventional ones and capable of large single-crystal growth have been devised, and their bulk single-crystal growth and properties are being demonstrated. Ongoing fundamental research, device fabrication, and testing will be conducted in parallel.
