Quantum criticality perspective on the charging of narrow quantum-dot levels.
Understanding the charging of exceptionally narrow levels in quantum dots in the presence of interactions remains a challenge within mesoscopic physics. We address this fundamental question in the generic model of a narrow level capacitively coupled to a broad one. Using bosonization we show that for arbitrary capacitive coupling charging can be described by an analogy to the magnetization in the anisotropic Kondo model, featuring a low-energy crossover scale that depends in a power-law fashion on the tunneling amplitude to the level. Explicit analytical expressions for the exponent are derived and confirmed by detailed numerical and functional renormalization-group calculations.
Kashcheyevs
V
V
Faculty of Physics and Mathematics, University of Latvia, Zeļļu street 8, Riga LV-1002, Latvia.
Karrasch
C
C
Hecht
T
T
Weichselbaum
A
A
Meden
V
V
Schiller
A
A