Lattice Effects on the Magnetoresistance in Doped LaMn<span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi mathvariant="normal">O</mi></mrow><mrow><mn>3</mn></mrow></msub></mrow></math></span>

H. Y. Hwang; S-W. Cheong; P. G. Radaelli; M. Marezio; B. Batlogg

doi:10.1103/PhysRevLett.75.914

Lattice Effects on the Magnetoresistance in Doped LaMn $O_{3}$

H. Y. Hwang, S-W. Cheong, P. G. Radaelli, M. Marezio, and B. Batlogg

Phys. Rev. Lett. 75, 914 – Published 31 July 1995

Abstract

A detailed study of doped LaMn $O_{3}$ with fixed carrier concentration reveals a direct relationship between the Curie temperature $T_{c}$ and the average ionic radius of the La site $〈 r_{A} 〉$ , which is varied by substituting different rare earth ions for La. With decreasing $〈 r_{A} 〉$ , magnetic order and significant magnetoresistance occur at lower temperatures with increasing thermal hysteresis, and the magnitude of the magnetoresistance increases dramatically. These results show that the notion of “double exchange” must be generalized to include changes in the Mn-Mn electronic hopping parameter as a result of changes in the Mn-O-Mn bond angle.

Received 22 March 1995

DOI:https://doi.org/10.1103/PhysRevLett.75.914

Authors & Affiliations

H. Y. Hwang^1,2, S-W. Cheong¹, P. G. Radaelli³, M. Marezio^1,4, and B. Batlogg¹

¹AT&T Bell Laboratories, Murray Hill, New Jersey 07974
²Joseph Henry Laboratories of Physics, Princeton University, Princeton, New Jersey 08544
³Institute Laue-Langevin, BP 156, 38042 Grenoble Cedex 9, France
⁴Laboratoire de Cristallographie, Centre National de la Recherche Scientifique-UJF, BP 166, 38042 Grenoble Cedex 9, France