Physical review. B, Condensed matter
Multichannel impurity scattering in a Tomonaga-Luttinger liquid
Yu-Liang Liu
Abstract
Using an elementary method, we demonstrate that (1) the duality of the correlation exponents near impurity site $x=0$ between ultraviolet and infrared fixed points is also valid for channel number larger than one; (2) the infrared fixed points ${\ensuremath{\delta}}_{c}^{i}=\ifmmode\pm\else\textpm\fi{}\ensuremath{\pi}/2$ do not correspond to two real half-infinity Tomonaga-Luttinger liquids even if the conductance is zero; (3) the electron's density of state at $x=0$ is enhanced compared with its neighbor ones; (4) as channel number is larger than (or equal to) two, the Fermi-edge singularity induced by backward scattering will be swept off by even small repulsive interaction of the electrons.