arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2006.07424cond-mat.str-elcond-mat.supr-con
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几何阻挫Pr $_{2}$ Ir $_{2}$ O $_{7}$中的非均匀近藤晶格

Inhomogeneous Kondo-lattice in geometrically frustrated Pr$_{2}$Ir$_{2}$O$_{7}$

Mariam Kavai, Joel Friedman, Kyle Sherman, Mingda Gong, Ioannis Giannakis, Samad Hajinazar, Haoyu Hu, Sarah E. Grefe, Justin Leshen, Qiu Yang, Satoru Nakatsuji,… 展开作者

Mariam Kavai, Joel Friedman, Kyle Sherman, Mingda Gong, Ioannis Giannakis, Samad Hajinazar, Haoyu Hu, Sarah E. Grefe, Justin Leshen, Qiu Yang, Satoru Nakatsuji, Aleksey N. Kolmogorov, Qimiao Si, Michael Lawler, Pegor Aynajian

摘要:

在烧绿石铱酸盐R $_{2}$ Ir $_{2}$ O $_{7}$(R =镧系元素)$^{1}$中,由局部Ir自旋的几何挫挫引起的磁涨落干扰了长程磁有序的形成.因此,Pr $_{2}$ Ir $_{2}$ O $_{7}$处于一个无调谐的反铁磁-顺磁量子临界点,并表现出一系列复杂的现象,包括近藤效应、双二次能带结构、金属自旋液体(MSL)和反常霍尔效应$^{2-5}$ .使用扫描隧道显微镜的光谱成像,辅以机器学习K-均值聚类分析,密度泛函理论和理论建模,我们探测Pr $_{2}$ Ir $_{2}$ O $_{7}$单晶中的局部电子态,并发现电子相分离。具有明确的近藤共振的纳米尺度区域与具有近藤破坏的非磁性金属相交织。值得注意的是,空间纳米级图案显示相关驱动的分形几何与幂律行为延长了25年,与接近临界点一致。我们的发现揭示了一种新的纳米调谐路线,即利用电子势的空间变化作为调整近藤纠缠和几何挫折之间的平衡的手段。

英文摘要:

Magnetic fluctuations induced by geometric frustration of local Ir-spins disturb the formation of long range magnetic order in the family of pyrochlore iridates, R$_{2}$Ir$_{2}$O$_{7}$ (R = lanthanide)$^{1}$. As a consequence, Pr$_{2}$Ir$_{2}$O$_{7}$ lies at a tuning-free antiferromagnetic-to-paramagnetic quantum critical point and exhibits a diverse array of complex phenomena including Kondo effect, biquadratic band structure, metallic spin-liquid (MSL), and anomalous Hall effect$^{2-5}$. Using spectroscopic imaging with the scanning tunneling microscope, complemented with machine learning K-means clustering analysis, density functional theory, and theoretical modeling, we probe the local electronic states in single crystal of Pr$_{2}$Ir$_{2}$O$_{7}$ and discover an electronic phase separation. Nanoscale regions with a well-defined Kondo resonance are interweaved with a non-magnetic metallic phase with Kondo-destruction. Remarkably, the spatial nanoscale patterns display a correlation-driven fractal geometry with power-law behavior extended over two and a half decades, consistent with being in proximity to a critical point. Our discovery reveals a new nanoscale tuning route, viz. using a spatial variation of the electronic potential as a means of adjusting the balance between Kondo entanglement and geometric frustration.

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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