SU(4) and SU(2) Kondo Effects in Carbon Nanotube Quantum Dots

Abstract

We study the SU(4) Kondo effect in carbon nanotube quantum dots, where doubly degenerate orbitals form 4-electron ``shells''. The SU(4) Kondo behavior is investigated for one, two and three electrons in the topmost shell. While the Kondo state of two electrons is quenched by magnetic field, in case of an odd number of electrons two types of SU(2) Kondo effect may survive. Namely, the spin SU(2) state is realized in the magnetic field parallel to the nanotube (inducing primarily orbital splitting). Application of the perpendicular field (inducing Zeeman splitting) results in the orbital SU(2) Kondo effect.

5 pages. Some material was previously posted in cond-mat/0608573, v2

References in corpus (4)

• Orbital Kondo effect in carbon nanotubes
• Nonequilibrium Singlet-Triplet Kondo Effect in Carbon Nanotubes
• Quantum phase transition in capacitively coupled double quantum dots
• Electronic Transport Spectroscopy of Carbon Nanotubes in a Magnetic Field

Cited by in corpus (10)

• Coupling of Spin and Orbital Motion of Electrons in Carbon Nanotubes
• Zero-bias conductance in carbon nanotube quantum dots
• Kondo effect in carbon nanotube quantum dots with spin-orbit coupling
• Current noise through a Kondo quantum dot in a SU(N) Fermi liquid state
• Many-Body Physics and Quantum Chaos
• Shot Noise in SU(N) Quantum Dot Kondo Effects
• Fermi liquid theory for SU(N) Kondo model
• Kondo screening cloud and the charge staircase in one-dimensional mesoscopic devices
• Ground State and Excitations of Quantum Dots with "Magnetic Impurities"
• Three-orbital Kondo effect in single quantum dot system with plural electrons