We present a detailed study for the finite-frequency current noise of a Kondo quantum dot in the presence of a magnetic field by using a recently developed real-time functional renormalization group approach [C. P. Moca, P. Simon, C. H. Chung, and G. Zaránd, Phys. Rev. B 83, 201303(R) (2011)PRBMDO1098-012110.1103/PhysRevB.83.201303]. The scaling equations are modified in an external magnetic field; the couplings and nonlocal current vertices become strongly anisotropic, and develop new singularities. Consequently, in addition to the natural emission threshold frequency, ω=|eV|, a corresponding singular behavior is found to emerge in the noise spectrum at frequencies ω≈|eV±B|. The predicted singularities are measurable with present-day experimental techniques.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - 29 Apr 2014|