Jammalamadaka S Narayana, Kuntz Sebastian, Berg Oliver, Kittler Wolfram, Kannan U Mohanan, Chelvane J Arout, Sürgers Christoph
Magnetic Materials and Device Physics Laboratory, Department of Physics, Indian Institute of Technology Hyderabad, Hyderabad 502 205, India.
Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang Gaede Str. 1, Karlsruhe, 76131, Germany.
Sci Rep. 2015 Sep 1;5:13621. doi: 10.1038/srep13621.
The remote control of the electrical conductance through nanosized junctions at room temperature will play an important role in future nano-electromechanical systems and electronic devices. This can be achieved by exploiting the magnetostriction effects of ferromagnetic materials. Here we report on the electrical conductance of magnetic nanocontacts obtained from wires of the giant magnetostrictive compound Tb0.3Dy0.7Fe1.95 as an active element in a mechanically controlled break-junction device. The nanocontacts are reproducibly switched at room temperature between "open" (zero conductance) and "closed" (nonzero conductance) states by variation of a magnetic field applied perpendicularly to the long wire axis. Conductance measurements in a magnetic field oriented parallel to the long wire axis exhibit a different behaviour where the conductance switches between both states only in a limited field range close to the coercive field. Investigating the conductance in the regime of electron tunneling by mechanical or magnetostrictive control of the electrode separation enables an estimation of the magnetostriction. The present results pave the way to utilize the material in devices based on nano-electromechanical systems operating at room temperature.
室温下通过纳米结远程控制电导率将在未来的纳米机电系统和电子设备中发挥重要作用。这可以通过利用铁磁材料的磁致伸缩效应来实现。在此，我们报告了在机械控制的断结装置中，将巨磁致伸缩化合物Tb0.3Dy0.7Fe1.95的导线用作活性元件所获得的磁性纳米接触的电导率。通过垂直于长导线轴施加磁场的变化，纳米接触在室温下可重复地在“开路”（零电导率）和“闭路”（非零电导率）状态之间切换。在平行于长导线轴的磁场中进行的电导率测量表现出不同的行为，其中电导率仅在接近矫顽场的有限磁场范围内在两种状态之间切换。通过对电极间距进行机械或磁致伸缩控制来研究电子隧穿 regime 中的电导率，能够估算磁致伸缩。目前的结果为在基于室温下运行的纳米机电系统的设备中利用这种材料铺平了道路。
