论文标题
绝缘子磁化和密度的量子振荡
Quantum Oscillations in the Magnetisation and Density of States of Insulators
论文作者
论文摘要
在Kondo绝缘子中观察$ 1/b $ - 周期性的行为SMB $ _6 $和YBB $ _ {12} $挑战了量子振荡（QO）必然来自金属中的费米表面的传统观念。我们最近对这种现象提出了理论，重点是在两个相反的光线和具有倒置带结构的杂交间隙的绝缘体模型上。我们表明，在与金属的明显对比中，所有可观察到的所有可观测物在相同频率上均具有相同频率的振荡，QO频率之间存在QO频率之间的特征差异。磁化振荡显示出来自所有被占领的Landau水平产生，并且表现出与未脑化情况相同的频率。 LE-DOS振荡来自无序系统中的间隙边缘状态，在低温下在两个不同的频率之间表现出BEAT模式。诱导的间隙状态导致在未脑化频率下对DOS产生额外的贡献。磁化和DOS振荡的温度依赖性在质上不同，并且都显示出与Lifshitz-Kosevich形式的明显偏差。我们还计算运输，以确保我们正在探测DC电阻率中的隔热趋势。
The observation of $1/B$-periodic behavior in Kondo insulators SmB$_6$ and YbB$_{12}$ challenges the conventional wisdom that quantum oscillations (QO) necessarily arise from Fermi surfaces in metals. We revisit recently proposed theories for this phenomena, focusing on a minimal model of an insulator with a hybridization gap between two opposite-parity light and heavy mass bands with an inverted band structure. We show that there are characteristic differences between the QO frequencies in the magnetization and the low-energy density of states (LE-DOS) of these insulators, in marked contrast with metals where all observables exhibit oscillations at the same frequency. The magnetization oscillations are shown to arise from all occupied Landau levels and exhibit the same frequency as the unhybridized case. The LE-DOS oscillations arise from gap-edge states in a disorder-free system and exhibit a beat pattern between two distinct frequencies at low temperature. Disorder induced in-gap states lead to an additional contribution to the DOS at the unhybridized frequency. The temperature dependence of the magnetization and DOS oscillations are qualitatively different and both show marked deviations from the Lifshitz-Kosevich form. We also compute transport to ensure that we are probing a regime with insulating upturns in the dc resistivity.
