Strain memory of the Verwey transition
Strain memory of the Verwey transition
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Verwey 转变的应变记忆
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
S. Gilder
中科院分区：
文献类型：
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作者：
L. Carporzen;S. Gilder
[1]我们研究了应力对纯的，化学计量的，合成的多畴磁铁矿和天然的多畴磁铁矿具有相对较低和较高的氧化程度的Verwey转变的影响。在压力释放后进行低温磁矩测量。我们的研究结果明确地表明，随着压力的增加，从1 K/GPa的化学计量的磁铁矿到3 K/GPa的高度氧化的磁铁矿的压力高达约5 GPa的Verwey转变温度的增加。过渡宽度加宽与化学计量的磁铁矿的应力增加，然后变得不那么宽的氧化增加，直到宽度是不变的高度氧化的磁铁矿的应力。热处理到700°C不会明显逆转这种效应，这可能使Verwey转变适合用作涉及高压（>1 GPa）的情况下的地质压力计，例如在陨石撞击坑中。提出了一个模型解释的结果。
[1] We studied the effects of stress on the Verwey transition for pure, stoichiometric, synthetic multidomain magnetite and for natural multidomain magnetite having both relatively low and high degrees of oxidation. Low-temperature measurements of the magnetic moments were carried out after pressure release. Our results unambiguously show an increase in the Verwey transition temperature with increasing pressure that ranges from 1 K/GPa for stoichiometric magnetite to 3 K/GPa for highly oxidized magnetite for pressures up to about 5 GPa. The transition width broadens with increasing stress for stoichiometric magnetite and then becomes less broad as oxidation increases until the width is invariant with respect to stress for highly oxidized magnetite. Heat treatment to 700°C does not appreciably reverse the effect, which could make the Verwey transition suitable for use as a geobarometer in cases where high pressures (>1 GPa) are involved, such as in meteorite impact craters. A model explaining the results is put forward.