Y. Fujiwara, S. Takemoto, K. Nakamura, K. Shimada, M. Suzuki, K. Hidaka, Y. Terai and M. Tonouchi:
"Ultrafast carrier-trapping in Er-doped and Er,O-codoped GaAs revealed by pump and probe technique"
Physica B 401-402 (2007) pp. 234-237.
S. Kimura, S. Emura, H. Ofuchi, Y. Zhou, S. Hasegawa and H. Asahi:
"Growth and Characterization of Ferromagnetic Cubic GaCrN: Structural and magnetic properties"
Journal of Crystal Growth 301-302 (2007) pp. 651-655.
S. Kobayashi, S. Shanthi, S. Kimura, Y. K. Zhou, S. Emura, S. Hasegawa and H. Asahi:
"Molecular-beam epitaxy growth and characterization of ferromagnetic cubic GaCrN on GaAs substrate"
Journal of Crystal Growth 308 (1) (2007) pp. 58-62.
Y. Fujiwara, K. Nakamura, S. Takemoto, J. Sugino, Y. Terai, M. Suzuki and M. Tonouchi:
"Direct observation of picosecond-scale energy-transfer processes in Er,O-codoped GaAs by pump-probe reflection technique"
Physics of Semiconductors, AIP Conference Proceedings, Vol. 893, edited by W. Jantsch and F. Schaffler (AIP, New York, 2007) pp. 245-246.
Y. Fujiwara, S. Takemoto, T. Tokuno, K. Hidaka, H. Ichida, M. Suzuki, Y. Terai, Y. Kanematsu and M. Tonouchi:
"Mechanism of excitation and relaxation in Er,O-codoped GaAs for 1.5 µm light-emitting devices with extremely stable wavelength"
Physica Status Solidi (a) 205(1) (2008) pp. 64-67.
S. Kimura, S. Emura, Y. Yamauchi, Y. K. Zhou, S. Hasegawa and H. Asahi:
"Low temperature molecular-beam epitaxy growth of cubic GaCrN"
Journal of Crystal Growth 310 (2008) pp. 40-46.
Y. K. Zhou, S.W. Choi, S. Emura, S. Hasegawa and H. Asahi:
Applied Physics Letters 92(6) (2008) p. 062505.
K. Shimada, Y. Terai, S. Takemoto, K. Hidaka, Y. Fujiwara, M. Suzuki and M. Tonouchi:
"Terahertz radiation from Er,O-codoped GaAs surface grown by organometallic vapor phase epitaxy"
Applied Physics Letters 92(11) (2008) p. 111115.
Y. Fujiwara:
"New approach to Er,O-codoped GaAs based light-emitting devices with extremely stable wavelength"
2007 European Materials Research Society Spring Meeting (E-MRS2007), C-8.5, Strasbourg, France, May 28-June 1 (2007).
H. Asahi, Y. K. Zhou, S. Emura and S. Hasegawa:
"MBE Growth and Characterization of Rare-Earth Doped Nitride Semiconductors for Spintronics"
2007 European Materials Research Society Spring Meeting (E-MRS2007), C-13.1, Strasbourg, France, May 28-June 1 (2007)
Y. Fujiwara:
"Injection-type light-emitting devices fabricated by atomically controlled doping of Er to GaAs"
Y. K. Zhou, S.W. Choi, S. Kimura, S. Emura, S. Hasegawa and H. Asahi:
"Enhancement of magnetic moment in GaGdN/GaN superlattice structure"
ChinaNANO 2007, P103, Beijing, China, June 4-6 (2007).
Y. K. Zhou, S.W. Choi, S. Kimura, S. Emura, S. Hasegawa and H. Asahi:
"High Gd concentration GaGdN grown at low temperature" SpinTech-IV, P19, Hawaii, USA, June 20-22 (2007).
Y. Fujiwara, S. Takemoto, M. Suzuki, K. Shimada, K. Hidaka, Y. Terai and M. Tonouchi:
"Ultrafast carrier-trapping in Er-doped and Er,O-codoped GaAs revealed by pump and probe transmission technique"
24th International Conference on Defects in Semiconductors (ICDS24), TO4-4, Albuquerque, USA, July 22-27 (2007).
K. Shimada, Y. Terai, S. Takemoto, M. Suzuki, M. Tonouchi, and Y. Fujiwara:
"Carrier dynamics in Er,O-codoped GaAs revealed by time-resolved terahertz emission measurements"
The Joint 32nd International Conference on Infrared and Millimeter Waves and the 15th International Conference on Terahertz Electronics (IRMMW-THz2007), TueP5-41, Cardiff, UK, September 2-7, 2007.
Y. K. Zhou, S.W. Choi, S. Kimura, S. Emura, S. Hasegawa and H. Asahi:
"Enhancement of magnetic moment in GaGdN/GaN superlattice structure"
Material Today Asia, Beijing, China, September 3-5 (2007).
S. Kimura, S. Emura, Y. Hiromura, Y.K. Zhou, S. Hasegawa and H. Asahi:
"Growth and characterization of InCrN and (In,Ga,Cr)N diluted magnetic semiconductors"
7th International Conference on Nitride Semiconductors, Las Vegas, Nevada, USA, September 16-21 (2007).
M. Fujisawa, A. Asakura, S. Okubo, H. Ohta and Y. Fujiwara:
"Electron spin resonance study of Er-concentration dependence on the local structure of the Er-centers in GaAs:Er,O"
Handai Nanoscience and Nanotechnology International Symposium ?Spin, Photonic, and Molecular Devices in Quantum limit-, P-2-11, Toyonaka, Osaka, September 26-28, 2007.
Y. Terai, K. Hidaka and Y. Fujiwara:
"Organometallic vapor phase epitaxy of Er,O-codoped GaAs using trisdipivaloylmethanatoerbium"
2nd International Symposium on Atomic Technology (ISAT2), P10, Awaji Island, Japan, October 1-2, 2007.
K. Shimada, S. Takemoto, K. Hidaka, Y. Terai, M. Tonouchi, and Y. Fujiwara:
"Ultrafast photoexcited carrier dynamics in GaAs:Er,O by pump and probe transmission spectroscopy"
34th International Symposium on Compound Semiconductors (ISCS 2007), MoD-P3, Kyoto, Japan, October 15-17, 2007.
A.Fujita, T. Tokuno, K. Hidaka, K. Fujii, K. Tachibana, H. Ichida, Y. Terai, Y. Kanematsu and Y. Fujiwara:
"Nonradiative processes at low temperature in Er,O-codoped GaAs grown by organometallic vapor phase epitaxy"
34th International Symposium on Compound Semiconductors (ISCS 2007), MoD-P4, Kyoto, Japan, October 15-17, 2007.
K. Fujii, K. Hidaka, D. Yamamoto, Y. Terai and Y. Fujiwara:
"GaAs emission from GaInP/Er,O-codoped GaAs/GaInP laser diodes grown by organometallic vapor Phase epitaxy"
34th International Symposium on Compound Semiconductors (ISCS 2007), TuA-II3, Kyoto, Japan, October 15-17, 2007.
M. Fujisawa, A. Asakura, S. Okubo, H. Ohta and Y. Fujiwara:
"Er-concentration dependence in GaAs:Er,O studied by X-band ESR"
Kobe University Frontier Technology Forum 2007 -Nanotechnology and Biotechnology for Next-Generation Photonics-, P16, Kobe, Japan, November 1-2 (2007).
M. Fujisawa, A. Asakura, S. Okubo, H. Ohta and Y. Fujiwara:
"Er-concentration Effect in GaAs:Er,O studied by Electron Spin Resonance"
A Joint Conference of the International Symposium on Electron Spin Science and the 46th Annual Meeting of the Society of Electron Spin Science and Technology, 1A11, Shizuoka, Japan, November 6-9 (2007).
K. Shimada, S. Takemoto, K. Hidaka, Y. Terai, M. Tonouchi and Y. Fujiwara:
"Ultrafast trapping processes of photoexcited carriers in Er,O-codoped GaAs revealed by pump and probe transmission technique"
A. Fujita, T. Tokuno, K. Hidaka, K. Fujii, K. Tachibana, H. Ichida, Y. Terai, Y. Kanematsu and Y. Fujiwara:
"Temperature dependence of Er-related PL intensity in Er,O-codoped GaAs"
Y. Hiromura, Y. Yamauchi, S. Kimura, S. Hasegawa and H. Asahi:
"Growth of GaCrN/AlN multiple quantum well structure by RF-MBE"
K. Fujii, K. Hidaka, D. Yamamoto, Y. Terai and Y. Fujiwara:
"GaAs lasing characteristics of GaInP/Er,O-codoped GaAs/GaInP light emitting devices grown by organometallic vapor phase epitaxy"
Y. Fujiwara:
"Atomically controlled rare-earth doping to III-V semiconductors and its application to new-type light-emitting devices"
K. Tokuda, S. Kimura, S. Emura, H. Tambo, Y. Hiromura, Y. K. Zhou, S. Hasegawa and H. Asahi:
"Coordination alignments at dopant Cr ion site in AlCrN"
Y. Hiromura, M. Takahashi, S. Kimura, H. Tambo, Y. K. Zhou, S. Emura, T. Nakamura, S. Hasegawa and H. Asahi:
"Soft X-ray Magnetic Circular Dichroism in GaGdN"
H. Tambo, S. Emura, S. Kimura, S. Hasegawa and H. Asahi:
"Crystal growth of GaCrN nanorods on Si substrates: local structure and magnetism"
G. S. Song, M. Kobayashi, J. I. Hwang, T. Kataoka, Y. Sakamoto, K. Ebata, A. Fujimori, T. Ohkochi, Y. Takeda, T. Okane, Y. Saitoh, H. Yamagam, F.-H. Chang, L. Lee, H.-J. Lin, D.-J. Huang, C. T. Chen, S. Kimura, M. Funakoshi, S. Hasegawa and H. Asahi:
"Photoemission and x-ray absorption study of Si-doped Ga1-xCrxN"
M. Fujisawa, A. Asakura, S. Okubo, H. Ohta and Y. Fujiwara:
"ESR study of Er-concentration effect in photoluminescence material GaAs:Er,O"
Y. K. Zhou, S. Kimura, Y. Hiromura, M. Takahashi, S. Emura, S. Hasegawa and H. Asahi:
"Magnetic and optical properties of high Gd concentration GaGdN grown at low temperatures"
"New development in rare-earth doped semiconductors: quantum properties revealed by control of atomic configuration"
S. Emura, S. Kimura, H. Tambo, Y. Hiromura, Y. K. Zhou, S. Hasegawa and H. Asahi:
"Deformation of CrN4 Cage in GaCrN Detected by X-ray Linear Dichroism"