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arXiv · 0908.0557

Theory and design of quantum cascade lasers in (111) n-type Si/SiGe

A. Valavanis·L. Lever·C. A. Evans·Z. Ikonić·R. W. Kelsall
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Abstract

Although most work toward the realization of group IV quantum cascade lasers (QCLs) has focused on valence-band transitions, there are many desirable properties associated with the conduction band. We show that the commonly cited shortcomings of n-type Si/SiGe heterostructures can be overcome by moving to the (111) growth direction. Specifically, a large band offset and low effective mass are achievable and subband degeneracy is preserved. We predict net gain up to lattice temperatures of 90 K in a bound-to-continuum QCL with a double-metal waveguide, and show that a Ge interdiffusion length of at least 8 angstroms across interfaces is tolerable.

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A. Valavanis, L. Lever, C. A. Evans, Z. Ikonić, R. W. Kelsall. 2009-08-04. Theory and design of quantum cascade lasers in (111) n-type Si/SiGe. https://doi.org/10.1103/physrevb.78.035420

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