Investigation of Energy Band Structures of InAs/GaSb and M Structure Superlattices
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摘要: 本文通过k·p方法研究了传统InAs/GaSb超晶格和M结构超晶格的能带结构。首先,计算了不同周期厚度的InAs/GaSb超晶格的能带结构,得到用于长波超晶格探测器吸收层的周期结构。然后,计算了用于超晶格长波探测器结构的M结构超晶格的能带结构,并给出长波InAs/GaSb超晶格与M结构超晶格之间的带阶。最后,基于能带结构,计算出长波超晶格与M结构超晶格的态密度,进而得出的载流子浓度(掺杂浓度)与费米能级的关系。这些材料参数可以为超晶格探测器结构设计提供基础。
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关键词:
- k·p方法 /
- InAs/GaSb超晶格 /
- M结构超晶格 /
- 能带结构 /
- 掺杂浓度
Abstract: In this study, the band structures of conventional InAs/GaSb and M structure super lattices are investigated using the k·p method. First, the band structures of InAs/GaSb super lattices with various period thickness are calculated, and the period structure used for a longwave super lattice detector is obtained. Subsequently, the band structure of the M structure super lattice, which is prevalently employed in longwave super lattice infrared detectors, is also calculated. The band offset between a longwave InAs/GaSb super lattice and M structure super lattice is provided. Furthermore, based on the band structures, the relationship between the carrier density (doping density) and the position of the Fermi level for longwave InAs/GaSb and M structure super lattices is obtained. This was followed by a density of states (DOS) calculation. These calculated material parameters can provide the foundation for designing super lattice infrared detectors.-
Key words:
- k·p method /
- InAs/GaSb superlattice /
- M structure super lattice /
- energy band structure /
- doping density
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表 1 14 MLs InAs/ 7 MLs GaSb超晶格和18 MLs InAs/ 3 MLs GaSb/ 5 MLs AlSb/ 3 MLs M结构超晶格的关键能带参数
Table 1. Critical energy band parameter of 14 MLs InAs/ 7 MLs GaSb superlattice and 18 MLs InAs/ 3 MLs GaSb/ 5 MLs AlSb/ 3 MLs M structure superlattice
Structure Effective energy
gap (Eg)/eVBottom of conduction
band (Ec)/eVTop of valence
band (Ev)/eVΔEc/meV ΔEv/meV 14 MLs InAs/ 7 MLs GaSb superlattice 0.1235 0.0701 -0.0534 -- -- 18 MLs InAs/ 3 MLs GaSb/ 5 MLs AlSb/ 3 MLs M structure superlattice 0.2133 0.0612 -0.1521 -8.9 -98.7 -
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