Rectification in one-dimensional electronic systems

Asymmetric current-voltage [I(V)] curves, known as the diode or rectification effect, in one-dimensional electronic conductors can have their origin from scattering off a single asymmetric impurity in the system. We investigate this effect in the framework of the Tomonaga-Luttinger model for electrons with spin. We show that electron interactions strongly enhance the diode effect and lead to a pronounced current rectification even if the impurity potential is weak. For strongly interacting electrons and not too small voltages, the rectification current I_r=[I(V)+I(−V)]∕2, measuring the asymmetry in the current-voltage curve, has a power-law dependence on the voltage with a negative exponent, I_r∼V^−∣z∣, leading to a bump in the current-voltage curve.