@article{oai:miyazaki-u.repo.nii.ac.jp:00004401,
 author = {Fukuyama, Atsuhiko and 福山, 敦彦 and 境, 健太郎 and Sakai, Kentaro and 明石, 義人 and Akashi, Yoshito and Ikari, Tetsuo and 碇, 哲雄 and Memon, Aftab},
 issue = {3},
 journal = {Journal of Applied Physics},
 month = {Feb},
 note = {The temperature variation of the piezoelectric photo-thermal （PPT） signal intensity of semi-insulating （SI） GaAs from 20 to 150 K was measured. Four peaks at 50, 70, 110, and 125 K were observed in the PPT signal. From the theoretical analysis based on the rate equations of electrons in the conduction band and deep levels, we concluded that the observed four peaks were due to the nonradiative electron transitions through EL6, EL7, EL15, and an unspecified deep level, respectively. Deep levels with extremely low concentration （10^<12> –10^<15>  cm^<−3> ） were clearly identified in SI GaAs by using the PPT method., The following article appeared in Journal of Applied Physics. 2/1/2001, Vol. 89 Issue 3, p1751 and may be found at http://dx.doi.org/10.1063/1.1336560},
 pages = {1751--1754},
 title = {Investigation of deep levels in semi-insulating GaAs by means of the temperature change piezoelectric photo-thermal measurements},
 volume = {89},
 year = {2001},
 yomi = {フクヤマ, アツヒコ and サカイ, ケンタロウ and アカシ, ヨシト and イカリ, テツオ}
}