Paleomagnetic recording fidelity of nonideal magnetic systems.
Paleomagnetic recording fidelity of nonideal magnetic systems.
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DOI：
10.1002/2014gc005249
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发表时间：
2014-06
期刊：
影响因子：
--
通讯作者：
Almeida TP
中科院分区：
文献类型：
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作者：
Muxworthy AR;Krása D;Williams W;Almeida TP
一套由电子束光刻产生的几乎相同的磁铁矿纳米点样品已被用于测试74-333 nm尺寸范围内颗粒的热磁记录保真度;岩石中最常见的粒度范围。除了控制晶粒尺寸，样品具有相同的颗粒间距，这意味着可以控制晶粒间的静磁相互作用。它们的磁滞参数表明颗粒被认为不是理想的磁记录器;然而，样品被发现是磁场方向的优秀热磁记录器。在标准的古强度实验中，它们也被发现是相对较好的场强记录器。样本强度均在预期答案的± 15%范围内，样本平均值在实际场的3%范围内。这些非理想磁系统已被证明是可靠的记录地磁场的方向和强度，即使他们的磁滞特性表明低于理想的磁性颗粒。非理想磁系统精确记录磁场方向弱场剩磁比强场剩磁更稳定
A suite of near-identical magnetite nanodot samples produced by electron-beam lithography have been used to test the thermomagnetic recording fidelity of particles in the 74–333 nm size range; the grain size range most commonly found in rocks. In addition to controlled grain size, the samples had identical particle spacings, meaning that intergrain magnetostatic interactions could be controlled. Their magnetic hysteresis parameters were indicative of particles thought not to be ideal magnetic recorders; however, the samples were found to be excellent thermomagnetic recorders of the magnetic field direction. They were also found to be relatively good recorders of the field intensity in a standard paleointensity experiment. The samples' intensities were all within ∼15% of the expected answer and the mean of the samples within 3% of the actual field. These nonideal magnetic systems have been shown to be reliable records of the geomagnetic field in terms of both direction and intensity even though their magnetic hysteresis characteristics indicate less than ideal magnetic grains. Nonideal magnetic systems accurately record field direction Weak-field remanences more stable than strong-field remanences