Magneto-transport studies of δ-doped III-V semiconductor quantum wells

• Main Authors: Kuo, Kwei Kuan, 郭桂冠
• Other Authors: Lo, Ikai
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/99087411413967112379

碩士 === 國立中山大學 === 物理研究所 === 84 === We intend to study the magneto-transport properties of two dimensional electron gas inδ-doped III-V semiconductors and to explore the electron's oscillations varied with the external magnetic field ( 0∼12 T ) Shubnikov-de Haas and Quantum Hall effect. The carrier concentration can be calculated precisely after Fourier transformation. The experimental result is as follows： Due to the negative persistent photo-conductivity effect, the carrier concentration decreased with theδ-doped Al0.5Ga0.5Sb/InAs quantum well at low temperature under illumination. Considering the δ-doped AlAs0.56Sb0.44/Ga0.47 In0.53As quantum well, the electron densities of the first and second subbands are 26.2 and 6.3 cm-2, respectively, of which increase to 29.2 and 7.2 cm-2 after low temperature's illumination. As a matter of fact, a positive persistent photo- conductivity effect may result after illumination. Other sample with similar structures to the former one has positive persistent photo-conductivity effect in view of measured Quantum Hall effect after illumination.