1 0 0 0 OA Exchange energy enhanced g-factors obtained from Landau fan diagrams at low magnetic fields
- 著者
- Nomura S. Tamura H. Yamaguchi M. Akazaki T. Hirayama Y.
- 出版者
- American Physical Society
- 雑誌
- Physical review B (ISSN:10980121)
- 巻号頁・発行日
- vol.87, no.8, pp.085318, 2013-02
- 被引用文献数
- 5 1
We report on measurement of the electron-hole effective g-factors (geff*) depending on electron filling factors ν from magnetophotoluminescence spectroscopy at low magnetic fields B<1 T in low electron density regime in a GaAs/Al0.33Ga0.67As-gated quantum well. Enhancement of geff* at odd ν is observed. The oscillatory behavior of geff* is compared with results of a theory that takes into account the lowest-order exchange interaction of the screened Coulomb interaction. Good agreement of the observed geff* with theoretical results is obtained except ν at around 3. The enhancement of geff* at even ν with decrease in electron density has not been observed.
1 0 0 0 OA Enhancement of electron and hole effective masses in back-gated GaAs/AlxGa1−xAs quantum wells
- 著者
- Nomura S. Yamaguchi M. Akazaki T. Tamura H. Maruyama T. Miyashita S. Hirayama Y.
- 出版者
- American Physical Society
- 雑誌
- Physical review B (ISSN:10980121)
- 巻号頁・発行日
- vol.76, no.20, pp.201306, 2007-11
- 被引用文献数
- 8 7
Both the electron and the optically created hole effective masses are found to be density dependent in a two-dimensional electron system of a GaAs/Al0.33Ga0.67As back-gated quantum well by magnetophotoluminescence spectroscopy. We show that the density-dependent electron effective mass increases with a decrease in the electron density (ns) to ns<1×1011 cm−2. It is found that the electron effective masses determined from the lowest and the second Landau levels are larger than those from the higher Landau levels. The hole effective mass is found to increase with a decrease in ns and the hole is found to localize at ns<3×1010 cm−2. We observe an upward convex curve of the photoluminescence peak energy at 2<ν<3 depending on the electron-hole distance divided by the magnetic length. These results clearly show the important roles of both electron-electron and electron-hole interactions in the recombination of a valence hole with a high-quality two-dimensional electron system.