Signatures of the Valley Kondo Effect in Si/Sige Quantum Dots

Authors

Mingyun Yuan, Dartmouth College
R. Joynt, University of Wisconsin-Madison
Zhen Yang, Dartmouth College
Chunyang Tang, Dartmouth College
D. E. Savage, University of Wisconsin-Madison
M. G. Lagally, University of Wisconsin-Madison
M. A. Eriksson, University of Wisconsin-Madison
A. J. Rimberg, Dartmouth College

Document Type

Article

Publication Date

7-2-2014

Publication Title

Physical Review B - Condensed Matter and Materials Physics

Department

Department of Physics and Astronomy

Abstract

We report measurements consistent with the valley Kondo effect in Si/SiGe quantum dots, evidenced by peaks in the conductance versus source-drain voltage that show strong temperature dependence. The Kondo peaks show unusual behavior in a magnetic field that we interpret as arising from the valley degree of freedom. The interplay of valley and Zeeman splittings is suggested by the presence of side peaks, revealing a zero-field valley splitting between 0.28 to 0.34 meV. A zero-bias conductance peak for nonzero magnetic field, a phenomenon consistent with valley nonconservation in tunneling, is observed in two samples.

DOI

10.1103/PhysRevB.90.035302

Dartmouth Digital Commons Citation

Yuan, Mingyun; Joynt, R.; Yang, Zhen; Tang, Chunyang; Savage, D. E.; Lagally, M. G.; Eriksson, M. A.; and Rimberg, A. J., "Signatures of the Valley Kondo Effect in Si/Sige Quantum Dots" (2014). Dartmouth Scholarship. 1929.
https://digitalcommons.dartmouth.edu/facoa/1929