ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
A study of infrared absorption due to intersubband transitions in p-type Si1−xGex/Si quantum wells has been performed. The influence of the hole envelope wave-function and the subband structure on the absorption characteristics is evaluated. In the calculation, the subbands in a SiGe strained layer are computed by using a bond orbital model, which combines the k⋅p and the tight-binding methods, with a strain Hamiltonian. Both of the Poisson and the Schrödinger equations are solved self-consistently to take into account a band-bending effect. The calculated quantum efficiency in a 40 A(ring) Si0.75Ge0.25/Si quantum well detector is compared favorably with an experimental result. The structural dependence of infrared absorption on quantum well width, doping and Ge content in a wavelength range of 3–15 μm is investigated. By varying a well width, our study reveals that a maximum absorption coefficient is obtained when the energy level of the excited-state subband is near the top of a quantum well. © 1995 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.359076
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