Probing spin-charge separation in a Tomonaga-Luttinger liquid.

Jompol, Y; Ford, C J B; Griffiths, J P; Farrer, I; Jones, G A C; Anderson, D; Ritchie, D A; Silk, T W et al. · Science · 2009

basic_science · Level V

Where this comes from

Abstract

In a one-dimensional (1D) system of interacting electrons, excitations of spin and charge travel at different speeds, according to the theory of a Tomonaga-Luttinger liquid (TLL) at low energies. However, the clear observation of this spin-charge separation is an ongoing challenge experimentally. We have fabricated an electrostatically gated 1D system in which we observe spin-charge separation and also the predicted power-law suppression of tunneling into the 1D system. The spin-charge separation persists even beyond the low-energy regime where the TLL approximation should hold. TLL effects should therefore also be important in similar, but shorter, electrostatically gated wires, where interaction effects are being studied extensively worldwide.