Temperature dependence of the anomalous exponent in Li(0.9)Mo(6)O(17) that reveals Luttinger Liquid behavior

Scanning tunneling spectroscopy (STS) has been used to study the Luttinger-liquid behavior of the purple bronze Li(0.9)Mo(6)O(17) in the temperature range 5K < T < 300K. In the entire temperature range the suppression of density of states at the Fermi-energy could be fitted very good by a model describing the tunneling into a Luttinger liquid at ambient temperature. The power-law exponent extracted from these fits reveals a significant increase above 200K. It changes from $\alpha$=0.6 at low temperature to $\alpha$=1.0 at room temperature.