Yamada T K, Bischoff M M J, Heijnen G M M, Mizoguchi T, Van Kempen H
NSRIM, University of Nijmegen, The Netherlands.
Phys Rev Lett. 2003 Feb 7;90(5):056803. doi: 10.1103/PhysRevLett.90.056803. Epub 2003 Feb 6.
We report the observation of a magnetic contrast of up to 20% in the scanning tunneling spectroscopy dI/dV maps obtained with Fe-coated tips on Mn(001) layers grown on an Fe(001) whisker at 370 K. These nanometer resolution microscopy results show that the layers couple antiferromagnetically. By normalizing the dI/dV curves by tunneling probability functions, we found a spin-dependent peak on the body-centered-tetragonal (bct) Mn(001) surface at +0.8 V, whose high spin polarization gives rise to the dI/dV map contrast. Band structure calculations allow one to identify the +0.8 V peak as due to two spin-polarized d(z(2)) surface states.
我们报告了在370K温度下，用涂有铁的针尖在生长于铁（001）晶须上的锰（001）层上获得的扫描隧道谱dI/dV图中观察到高达20%的磁对比度。这些纳米分辨率的显微镜结果表明，这些层呈现反铁磁耦合。通过用隧穿概率函数对dI/dV曲线进行归一化，我们在体心四方（bct）锰（001）表面+0.8V处发现了一个自旋相关峰，其高自旋极化导致了dI/dV图的对比度。能带结构计算使人们能够将+0.8V的峰确定为由两个自旋极化的d(z(2))表面态引起。
