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Magnetically tunable Kondo-Aharonov-Bohm effect in a triangular quantum dot

Department of Physics, Ben-Gurion University of the Negev, Be'er Sheva`, Southern District, Israel
Physical Review Letters (Impact Factor: 7.73). 03/2006; 96(4):046601. DOI: 10.1103/PhysRevLett.96.046601
Source: PubMed

ABSTRACT The role of discrete orbital symmetry in mesoscopic physics is manifested in a system consisting of three identical quantum dots forming an equilateral triangle. Under a perpendicular magnetic field, this system demonstrates a unique combination of Kondo and Aharonov-Bohm features due to an interplay between continuous [spin-rotation SU(2)] and discrete (permutation C3v) symmetries, as well as U(1) gauge invariance. The conductance as a function of magnetic flux displays sharp enhancement or complete suppression depending on contact setups.

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