Institut Charles Gerhardt de Montpellier UMR 5253, Université de Montpellier, 34095, Montpellier Cedex 5, France.
Laboratoire de Chimie de Coordination UPR 8241, CNRS, 31007, Toulouse Cedex 4, France.
Adv Mater. 2017 Dec;29(46). doi: 10.1002/adma.201703073. Epub 2017 Oct 25.
A promising and original method to study the spin-transition in bistable spin-crossover (SCO) materials using a magnetoresistive multiring sensor and its self-generated magnetic field is reported. Qualitative and quantitative studies are carried out combining theoretical and experimental approaches. The results show that only a small part of matter dropped on the sensor surface is probed by the device. At a low bias-current range, the number of detected nanoparticles depends on the amplitude of the current. However, in agreement with the theoretical model, the stray voltage from the particles is proportional to the current squared. By changing both the bias current and the concentration of particle droplet, the thermal hysteresis of an ultrasmall volume, 1 × 10 mm , of SCO particles is measured. The local probe of the experimental setup allows a highest resolution of 4 × 10 emu to be reached, which is never achieved by experimental methods at room temperature.
本文报道了一种使用磁电阻多环传感器及其自生磁场研究双稳自旋交叉（SCO）材料自旋转变的很有前途和原创的方法。通过理论和实验相结合的方法进行了定性和定量研究。结果表明，只有一小部分落在传感器表面的物质被该器件探测到。在低偏置电流范围内，检测到的纳米颗粒数量取决于电流的幅度。然而，与理论模型一致的是，颗粒的杂散电压与电流的平方成正比。通过改变偏置电流和颗粒液滴的浓度，测量了超小体积（1×10mm）SCO 颗粒的热滞后。实验装置的局部探针允许达到最高分辨率为 4×10emu，这是在室温下从未通过实验方法实现的。
