Terahertz magneto-transport measurements in underdoped PCCO and comparison with ARPES

We present magneto-transport measurements performed on underdoped PCCO at THz frequencies as a function of temperature and doping. A rapidly decreasing Hall mass is observed as the doping is reduced consistent with the formation of small electron Fermi pockets. However, both dc and infrared (IR) magneto-transport data strongly deviate from the predictions of transport theory in the relaxation time approximation (RTA) based on angular resolved photoemission data. The Hall mass is observed to increase continuously with increasing temperature with no signature at the Neel temperature. In the paramagnetic state, the temperature dependence of the Hall mass is consistent with current vertex corrections to the Hall conductivity due to magnetic fluctuations as observed in overdoped PCCO. Possible causal mechanisms for the discrepancy between transport theory within the RTA and the magneto-transport data are discussed.Comment: 7 pages, 2 figures, 1 tabl