TY - JOUR
T1 - Kondo Effect in Single Quantum Dot Systems - Study with Numerical Renormalization Group Method
AU - Izumida, Wataru
AU - Sakai, Osamu
AU - Shimizu, Yukihiro
PY - 1998/7
Y1 - 1998/7
N2 - The tunneling conductance is calculated as a function of the gate voltage in wide temperature range for the single quantum dot systems with Coulomb interaction. We assume that two orbitals are active for the tunneling process. We show that the Kondo temperature for each orbital channel can be largely different. The tunneling through the Kondo resonance almost fully develops in the region T ≲ 0.1TK*, ∼ 0.2TK*, where TK* is the lowest Kondo temperature when the gate voltage is varied. At high temperatures the conductance changes to the usual Coulomb oscillations type. In the intermediate temperature region, the degree of the coherency of each orbital channel is different, so strange behaviors of the conductance can appear. For example, the conductance once increases and then decreases with temperature decreasing when it is suppressed at T = 0 by the interference cancellation between different channels. The interaction effects in the quantum dot systems lead the sensitivities of the conductance to the temperature and to the gate voltage.
AB - The tunneling conductance is calculated as a function of the gate voltage in wide temperature range for the single quantum dot systems with Coulomb interaction. We assume that two orbitals are active for the tunneling process. We show that the Kondo temperature for each orbital channel can be largely different. The tunneling through the Kondo resonance almost fully develops in the region T ≲ 0.1TK*, ∼ 0.2TK*, where TK* is the lowest Kondo temperature when the gate voltage is varied. At high temperatures the conductance changes to the usual Coulomb oscillations type. In the intermediate temperature region, the degree of the coherency of each orbital channel is different, so strange behaviors of the conductance can appear. For example, the conductance once increases and then decreases with temperature decreasing when it is suppressed at T = 0 by the interference cancellation between different channels. The interaction effects in the quantum dot systems lead the sensitivities of the conductance to the temperature and to the gate voltage.
KW - Coulomb oscillations
KW - Kondo effect
KW - Quantum dot
KW - Tunneling
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U2 - 10.1143/JPSJ.67.2444
DO - 10.1143/JPSJ.67.2444
M3 - Article
AN - SCOPUS:0032356639
VL - 67
SP - 2444
EP - 2454
JO - Journal of the Physical Society of Japan
JF - Journal of the Physical Society of Japan
SN - 0031-9015
IS - 7
ER -