IngentaConnect Magnetic properties and the phase diagram of La [iopmath latex="$...

Authors: Paraskevopoulos M.¹; Mayr F.¹; Hemberger J.¹; Loidl A.¹; Heichele R.²; Maurer D.²; Mller V.²; Mukhin A.A.³; Balbashov A.M.⁴

Source: Journal of Physics: Condensed Matter, Volume 12, Number 17, 2000 , pp. 3993-4011(19)

Publisher: Institute of Physics Publishing

Abstract:

We report on susceptibility, magnetization, magnetoresistance, and ultrasonic studies of La [iopmath latex="$_{1-x}{\rm Sr}_{x}{\rm MnO}_{3}$"] _1-xSr_xMnO₃ [/iopmath] for [iopmath latex="$x\leq 0.2$"] x0.2 [/iopmath] . The magnetic susceptibilities in the different high-temperature paramagnetic phases are studied in detail. We provide experimental evidence for the occurrence of short-range ferromagnetic order within the paramagnetic phase. Furthermore, we can exclude the possibility of electronic phase separation for [iopmath latex="$x\lt 0.1$"] x<0.1 [/iopmath] . Variable-range-hopping conductivity dominates in the paramagnetic and magnetically ordered phases. From the anomalies at the structural and magnetic phase transitions, we arrive at a phase diagram which shows a ferromagnetic and insulating ground state for [iopmath latex="$0.1\leq x\leq 0.15$"] 0.1x0.15 [/iopmath] , followed by a canted antiferromagnetic phase at higher temperatures. The ferromagnetic transition is strongly coupled to a structural transition from a Jahn-Teller-distorted phase to a pseudocubic orthorhombic phase and is accompanied by the appearance of large positive magnetoresistance effects. We interpret the rich phase diagram close to [iopmath latex="$x=1/8$"] x = 1/8 [/iopmath] in terms of orbital ordering, due to an interplay of superexchange interactions and Jahn-Teller distortions.

Language: English

Document Type: Miscellaneous

Affiliations: 1: Experimentalphysik V, Elektronische, Korrelationen und Magnetismus, Institut f?r Physik, Universit?t Augsburg, D-86159 Augsburg, Germany 2: Experimentalphysik III, Institut f?r Physik, Universit?t Augsburg, D-86159 Augsburg, Germany 3: Moscow Power Engineering Institute, 105835 Moscow, Russia 4: General Physics Institute of the Russian Academy of Sciences, 117942 Moscow, Russia

The full text electronic article is available for purchase. You will be able to download the full text electronic article after payment.

$42.00 plus tax Refund Policy

Magnetic properties and the phase diagram of La [iopmath latex="$_{1-x}$"] 1-x [/iopmath] Sr [iopmath latex="$_{x}$"] x [/iopmath] MnO3 for [iopmath latex="$x \leq0.2$"] x0.2 [/iopmath]

Magnetic properties and the phase diagram of La [iopmath latex="$_{1-x}$"] _1-x [/iopmath] Sr [iopmath latex="$_{x}$"] _x [/iopmath] MnO₃ for [iopmath latex="$x \leq0.2$"] x0.2 [/iopmath]