arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 0709.1265cond-mat.mes-hallcond-mat.str-el
收藏

Al_{0.13} Ga_{0.87} As量子阱中大Skyrmion的NMR研究

NMR Study of Large Skyrmions in Al_{0.13}Ga_{0.87}As Quantum Wells

V. F. Mitrović, M. Horvatić, C. Berthier, S. A. Lyon, M. Shayegan

摘要:

报道了在朗道能级填充因子$ν=1$附近的多个(30)Al $_{0.13}$ Ga $_{0.87}$ As量子阱样品的核磁共振(NMR)研究。在这些Al $_{0.13}$ Ga $_{0.87}$ As量子阱中,有效$g$因子几乎为零。这可能导致两种效应:消失的电子极化$(P)$和由大量自旋组成的skyrmionic激发。由于小的$P$值导致来自QW和势垒的NMR信号重叠,因此采用特殊技术来区分这两个信号。量子阱信号对应于小的、负的和非常宽的自旋极化分布,其表现出热诱导去极化。这样的分布可以归因于样品的不均匀性和/或大的skyrmions,后者的可能性是由非常快的$T_{2}^{-1}$率的观察青睐。

英文摘要:

A nuclear magnetic resonance (NMR) study is reported of multiple (30) Al$_{0.13}$Ga$_{0.87}$As quantum well (QW) sample near the Landau level filling factor $ν=1$. In these Al$_{0.13}$Ga$_{0.87}$As QWs the effective $g$ factor is nearly zero. This can lead to two effects: vanishing electronic polarization $(P)$ and skyrmionic excitations composed of a huge number of spins. As small $P$ values cause an overlap of the NMR signals from the QW and barriers, a special technique was employed to allow these two signals to be distinguished. The QW signal corresponds to a small, negative, and very broad distribution of spin polarization that exhibits thermally induced depolarization. Such a distribution can be attributed to sample inhomogeneities and/or to large skyrmions, the latter possibility being favored by observation of a very fast $T_{2}^{-1}$ rate.

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。

↑