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Formation of three-particle clusters in hetero-junctions and MOSFET structures

E. P. Nakhmedov·K. Morawetz
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Abstract

A novel interaction mechanism in MOSFET structures and $GaAs/AlGaAs$ hetero-junctions between the zone electrons of the two-dimensional (2D) gas and the charged traps on the insulator side is considered. By applying a canonical transformation, off-diagonal terms in the Hamiltonian due to the trapped level subsystem are excluded. This yields an effective three-particle attractive interaction as well as a pairing interaction inside the 2D electronic band. A type of Bethe- Goldstone equation for three particles is studied to clarify the character of the binding and the energy of the three-particle bound states. The results are used to offer a possible explanation of the Metal-Insulator transition recently observed in MOSFET and hetero-junctions.

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E. P. Nakhmedov, K. Morawetz. 2004-03-05. Formation of three-particle clusters in hetero-junctions and MOSFET structures. https://doi.org/10.1103/physrevb.66.195333

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