Article

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: 7.51). 03/2006; 96(4):046601. DOI: 10.1103/PhysRevLett.96.046601
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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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Available from: Y. Avishai, Feb 12, 2014
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    • "In the absence of a magnetic field, the currents through the tunneling channels simply add, but in the presence of a perpendicular magnetic field B more complicated superposition pattern arises due to the Aharonov-Bohm effect. Besides, the field B introduces charge chirality into the scheme of classification of electron states of the CQD [34,35]. This type of chirality arises because an electron acquires a U(1) gauge phase / 3 φ = Φ at each tunneling hopping event. "
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