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arXiv 1507.08474cond-mat.mes-hallcond-mat.mtrl-scicond-mat.str-el
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量子自旋隧穿与近藤效应的竞争

Competition between quantum spin tunneling and Kondo effect

D. Jacob, J. Fernández-Rossier

摘要:

量子自旋隧穿(QST)和近藤效应是两种截然不同的量子现象,它们对量子化自旋产生相同的效应,即磁化淬灭。然而,这种猝灭的性质是非常不同的,使得QST和近藤效应相互竞争。重要的是,QST和Kondo都在光谱函数中产生了非常典型的特征,可以通过单自旋扫描隧道光谱来测量,从而可以探测从一个区域到另一个区域的交叉。我们模拟这种交叉,以及由此产生的变化,在运输,使用非微扰处理的广义安德森模型,包括磁各向异性,导致量子自旋隧道。我们预测,在零磁场下,整数自旋可以具有由量子自旋隧穿驱动的分裂近藤峰。

英文摘要:

Quantum spin tunneling (QST) and Kondo effect are two very different quantum phenomena that produce the same effect on quantized spins, namely, the quenching of their magnetization. However, the nature of this quenching is very different so that QST and Kondo effects compete with each other. Importantly, both QST and Kondo produce very characteristic features in the spectral function that can be measured by means of single spin scanning tunneling spectroscopy that makes it possible to probe the crossover from one regime to the other. We model this crossover, and the resulting changes in transport, using a non-perturbative treatment of a generalized Anderson model including magnetic anisotropy that leads to quantum spin tunneling. We predict that, at zero magnetic field, integer spins can feature a split-Kondo peak driven by quantum spin tunneling.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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