Tsukazaki, A., Ohtomo, A., Kawasaki, M., Akasaka, S., Yuji, H., Tamura, K., ...
We report measurements of the spin susceptibility and the electron effective mass for two-dimensional electrons confined at the interfaces of MgxZn1-xO/ZnO single heterostructures (x = 0.05, 0.08,...
Shifting donor-acceptor photoluminescence in N-doped ZnO (2006)
Makino, Takayuki, Tsukazaki, A., Ohtomo, A., Kawasaki, M., Koinuma, H.
We have grown nitrogen-doped ZnO films grown by two kinds of epitaxial methods on lattice-matched ScAlMgO$_4$ substrates. We measured the photoluminescence (PL) of the two kinds of ZnO:N layers in...
Makino, T., Saito, K., Ohtomo, A., Kawasaki, M., Senger, R. T., Bajaj, K. K.
Localization dynamics of excitons was studied for ZnO/MgZnO and CdZnO/MgZnO quantum wells (QW). The experimental photoluminescence (PL) and absorption data were compared with the results of Monte...
Majority-Carrier Mobilities in Undoped and \textit{n}-type Doped ZnO Epitaxial Layers (2005)
Makino, T., Segawa, Y., Tsukazaki, A., Ohtomo, A., Kawasaki, M.
Transparent and conductive ZnO:Ga thin films are prepared by laser molecular-beam epitaxy. Their electron properties were investigated by the temperature-dependent Hall-effect technique. The 300-K...
Spectral shape analysis of ultraviolet luminescence in \textit{n}-type ZnO:Ga (2005)
Makino, T., Segawa, Y., Yoshida, S., Tsukazaki, A., Ohtomo, A., Kawasaki, M., ...
Thin films of laser molecular-beam epitaxy grown \textit{n}-type Ga-doped ZnO were investigated with respect to their optical properties. Intense room-temperature photoluminescence (PL) in the...
Analysis on reflection spectra in strained ZnO thin films (2005)
Makino, T., Segawa, Y., Kawasaki, M., Ohtomo, A.
Thin films of laser molecular-beam epitaxy grown ZnO films were studied with respect to their optical properties. 4-K reflectivity was used to analyze various samples grown at different biaxial...
Electron transport in ZnO thin films (2005)
Makino, T., Segawa, Y., Tsukazaki, A., Ohtomo, A., Kawasaki, M.
Epitaxial, n-type ZnO films grown by a laser molecular-beam epitaxy method were investigated by the temperature-dependent Hall-effect technique. The 300-K carrier concentration and mobility were...
Makino, T., Segawa, Y., Yoshida, S., Tsukazaki, A., Ohtomo, A., Kawasaki, M.
We investigated the optical properties of epitaxial \textit{n}-type ZnO films grown on lattice-matched ScAlMgO$_4$ substrates. As the Ga doping concentration increased up to $6 \times 10^{20}$...
Modeling and simulation of polycrystalline ZnO thin-film transistors (2003)
Hossain, Faruque M., Nishii, J., Takagi, S., Ohtomo, A., Fukumura, T., Fujioka, H., ...
Thin film transistors (TFTs) made of transparent channel semiconductors such as ZnO are of great technological importance, because their insensitivity to visible light makes device structures simple....
Resonant exciton second-harmonic generation in self-assembled ZnO microcrystallite thin films (2003)
Zhang, X. Q., Tang, Zi-Kang, Kawasaki, M., Ohtomo, A., Koinuma, H.
Second-harmonic generation has been studied for fundamental wavelengths from 720 to 1100 nm on high-quality ZnO thin films deposited on sapphire substrates by laser molecular beam epitaxy. The...
Phonon replicas in ZnO/ZnMgO multi-quantum wells. (2002)
Sun, H. D., Segawa, Y., Kawasaki, M., Ohtomo, A., Tamura, K., Koinuma, H.
The photoluminescence properties of ZnO/ZnMgO multiquantum wells have been investigated by continuous and time-resolved photoluminescence spectra at various temperatures. Strong first-order and...
Enhancement of exciton binding energies in ZnO/ZnMgO multi-quantum wells. (2002)
Makino, T., Segawa, Y., Kawasaki, M., Ohtomo, A., Tamura, K., Koinuma, H., ...
The effect of confinement on the exciton binding energies has been systematically investigated for two series of ZnO/ZnMgO multiquantum wells with various well widths and barrier heights. The exciton...
Makino, T., Tuan, N. T., Sun, H. D., Chia, C. H., Segawa, Y., Kawasaki, M., ...
We report on temperature dependence of excitonic photoluminescence (PL) from ZnO/(Mg, Zn)O multiple quantum wells (MQWs). Two kinds of MQWs having different barrier heights grown by laser...
Biexciton emission from ZnO/Zn0.74Mg0.26O multi-quantum wells. (2001)
Sun, H. D., Makino, T., Tuan, N. T., Segawa, Y., Kawasaki, M., Ohtomo, A., ...
Luminescence due to the radiative recombination of localized biexcitons has been observed at low temperature (5 K) in ZnO/Zn0.74Mg0.26O multiquantum wells grown by laser-molecular-beam epilaxy on a...
Sun, H. D., Makino, T., Tuan, N. T., Segawa, Y., Kawasaki, M., Ohtomo, A., ...
The excitonic properties of high-quality ZnO/Zn0.88Mg0.12O multiquantum wells grown by laser-molecular-beam epitaxy were investigated using temperature-dependent optical absorption spectra from 5 K...
Makino, T., Tuan, N. T., Sun, H. D., Chia, C. H., Segawa, Y., Kawasaki, M., ...
We report on temperature dependence of excitonic photoluminescence (PL) from ZnO/(Mg, Zn)O multiple quantum wells (MQWs). Two kinds of MQWs having different barrier heights grown by laser...
Makino, T., Chia, C. H., Tuan, N. T., Sun, H. D., Segawa, Y., Kawasaki, M., ...
We report on the optical properties of ZnO/(Mg, Zn)O multiple quantum wells (MQWs) on lattice-matched ScAlMgO4 substrates fabricated by laser molecular-beam epitaxy. As the well layer thickness...
Sun, H. D., Makino, T., Tuan, N. T., Segawa, Y., Tang, Z. K., Wong, G. K. L., ...
The mechanism of ultraviolet stimulated emission was investigated in ZnO/ZnMgO multiquantum wells. Stimulated emission induced by exciton–exciton scattering occurred throughout a range of...