Temperature and Pressure Effects on the Resistivity of the Manganese Oxides.pdfVIP

Temperature and Pressure Effects on the Resistivity of the Manganese Oxides Hae-Young Kee and Jongbae Hong Department of Physics Education, Seoul National University, Seoul 151-742, Korea 6 9 9 1 Abstract n u J The temperature and pressure effects on the resistivity of the manganese ox- 2 1 ides are studied analytically via the Kondo lattice model with a strong Hund’s 1 v coupling. We obtain analytically the single-particle density of states on the 9 7 Bethe lattice in the large connectivity limit using the analytical variant of the 0 6 0 dynamic Lanczos method. From the density of states for the doped system, 6 9 we obtain resistivity and show resistivity drop when temperature crosses the / t a m magnetic transition point. We also demonstrate the effect of pressure both - d below and above the transition temperature. n o 75.70.Pa, 75.30.Mb, 72.15.Gd c : v i X r a Typeset using REVT X E 1 I. INTRODUCTION Though manganese oxides had been studied extensively during 50’s and 60’s, [1] the hole-doped manganese oxides La A MnO (A = Ca, Ba, P b, or Sr) have recently driven a 1−x x 3 considerable attention due to not only the phenomenon of giant magnetoresistance (GMR) [2] but also various interesting physical properties such as doping induced metal-insulator transition, antiferromagnetic