Fluctuation-induced hopping and spin-polaron transport

被引：13

作者：

Wegener, LGL ^{[1
]}

Littlewood, PB ^{[1
]}

机构：

[1] Univ Cambridge, Cavendish Lab, TCM, Cambridge CB3 0HE, England

来源：

PHYSICAL REVIEW B | 2002年 / 66卷 / 22期

关键词：

D O I：

10.1103/PhysRevB.66.224402

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We study the motion of free magnetic polarons in a paramagnetic background of fluctuating local moments. The polaron can tunnel only to nearby regions of local moments when these fluctuate into alignment. We propose this fluctuation-induced hopping as a transport mechanism for the spin polaron. We calculate the diffusion constant for fluctuation-induced hopping from the rate at which local moments fluctuate into alignment. The electrical resistivity is then obtained via the Einstein relation. We suggest that the proposed transport mechanism is relevant in the high-temperature phase of the Mn pyrochlore "colossal magnetoresistance" compounds and EuB6.

引用

页码：1 / 8

页数：8

共 32 条

[1]

ALAGUILLAUME CB, 1993, PHYS STATUS SOLIDI B, V175, P369

[2] 139La NMR in lanthanum manganites:: Indication of the presence of magnetic polarons from spectra and nuclear relaxations [J].

Allodi, G ;

De Renzi, R ;

Guidi, G .

PHYSICAL REVIEW B, 1998, 57 (02) :1024-1034

[3] Room temperature magnetoresistance and cluster-glass behavior in the Tl2-xBixMn2O7 (0≤x≤0.5) pyrochlore series [J].

Alonso, JA ;

Martínez, JL ;

Martínez-Lope, MJ ;

Casais, MT ;

Fernández-Díaz, MT .

PHYSICAL REVIEW LETTERS, 1999, 82 (01) :189-192

[4] Unprecedented magnetoresistance in Cd-substituted Tl2Mn2O7 pyrochlores [J].

Alonso, JA ;

Velasco, P ;

Martínez-Lope, MJ ;

Casais, MT ;

Martínez, JL ;

Fernández-Díaz, MT ;

de Paoli, JM .

APPLIED PHYSICS LETTERS, 2000, 76 (22) :3274-3276

[5] Isotope effect for the penetration depth in superconductors [J].

Bill, A ;

Kresin, VZ ;

Wolf, SA .

PHYSICAL REVIEW B, 1998, 57 (17) :10814-10824

[6] SPIN CORRELATION FUNCTIONS AT HIGH TEMPERATURES [J].

BLUME, M ;

HUBBARD, J .

PHYSICAL REVIEW B, 1970, 1 (09) :3815-&

[7] Stability and dynamics of free magnetic polarons [J].

Calderón, MJ ;

Brey, L ;

Littlewood, PB .

PHYSICAL REVIEW B, 2000, 62 (05) :3368-3371

[8] Stochastic problems in physics and astronomy [J].

Chandrasekhar, S .

REVIEWS OF MODERN PHYSICS, 1943, 15 (01) :0001-0089

[9] BROWNIAN MOTION, DYNAMICAL FRICTION, AND STELLAR DYNAMICS [J].

CHANDRASEKHAR, S .

REVIEWS OF MODERN PHYSICS, 1949, 21 (03) :383-388

[10] Giant magnetoresistance in pyrochlore Tl2-xInxMn2O7 [J].

Cheong, SW ;

Hwang, HY ;

Batlogg, B ;

Rupp, LW .

SOLID STATE COMMUNICATIONS, 1996, 98 (02) :163-166

← 1 2 3 4 →