k . p finite difference method for semiconductor heterostructures

• Main Authors: Chau, Zih-Ming, 趙志明
• Other Authors: Chiang, Jih-Chen
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/44948476903637042063

碩士 === 國立中山大學 === 物理研究所 === 84 === We have developed a six-band k．p finite difference method (KPFD) to calculate the electronic band structures of InAs-GaSb super- lattices and AlSb-GaSb-InAs-GaSb-AlSb quantum wells. The simple theoretical method combines the virtues of the envelope- function (k．p) and bond-orbital model. All interaction parameters involved are directly related to parameters for describing bulk bands near the zone center in the bond-orbital model or k．p model. The method can reproduce fairly accurate bulk band structure near the center of the two-dimensional Brillouin zone when we properly choose the interaction parameters and the dis- tance between two adjacent pseudo- layers. For intrinsic InAs-GaSb superlattices, we don't find truly semimetallic band structure. At low temperature(∼4.2k), the critical InAs thickness for a zero-gap semiconductor result is approximately 120 A. The evolution of the InAs-GaSb band structure with increasing periodicity is calculated and found to be in excellent agreement with previous NBO (nearest neighbor bond-orbital model) results. In AlSb-GaSb-InAs-GaSb- AlSb quantum wells, we shall demonstrate that the semiconductor- semimetal transition does exist in this hole-electron-hole quantum wells systems.