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Conductance quantization in etched Si/SiGe quantum point contacts

G. Scappucci·L. Di Gaspare·E. Giovine·A. Notargiacomo·R. Leoni·F. Evangelisti
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Abstract

We fabricated strongly confined Schottky-gated quantum point contacts by etching Si/SiGe heterostructures and observed intriguing conductance quantization in units of approximately 1e2/h. Non-linear conductance measurements were performed depleting the quantum point contacts at fixed mode-energy separation. We report evidences of the formation of a half 1e2/h plateau, supporting the speculation that adiabatic transmission occurs through 1D modes with complete removal of valley and spin degeneracies.

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G. Scappucci, L. Di Gaspare, E. Giovine, A. Notargiacomo, R. Leoni, F. Evangelisti. 2006-06-21. Conductance quantization in etched Si/SiGe quantum point contacts. https://doi.org/10.1103/physrevb.74.035321

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