Title

Raman study of the Verwey transition in magnetite at high-pressure and low-temperature: Effect of Al doping

Document Type

Article

Publication Date

8-15-2012

Abstract

We employed Raman spectroscopy to investigate how the hydrostatic pressure affects the temperature of the Verwey transition in pure (Fe 3O 4) and Al-doped (Fe 2.8Al 0.2O 4) magnetite. In both samples, pressure suppresses the transition. The Al-doped sample displays no transition above 8 GPa. We do not observe such discontinuity in a pure magnetite, which suggests that the discontinuity is doping driven. Our Clausius-Clapeyron formula based analysis of the pressure-transition temperature dependence is in excellent agreement with our data in pure magnetite. The Al doping leads to a smaller entropy change and larger volume expansion consistent with partial charge ordering at the transition. © 2012 American Institute of Physics.

Publication Title

Journal of Applied Physics

Volume

112

Issue

4

Digital Object Identifier (DOI)

10.1063/1.4747834

ISSN

00218979

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