Semiconductor lasers without population inversion
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Updated: Jun 19, 2026

Laser-induced Forward Transfer for Flip-chip Packaging of Single Dies
Published on: March 20, 2015
Abstract:
We propose a new scheme for lasing without population inversion that utilizes interferences in double-quantum-well intersubband transitions. In contrast to the previous inversionless laser schemes based on atomic systems, the new proposal permits us to use band-gap engineering to choose the subband energies, coupling strengths, and decay rates, as desired, and permits us to create a laser system that does not require population inversion. We present detailed calculations on a specific scheme and discuss possible extensions.
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