Observation of an antiferromagnetic quantum critical point in high-purity LaNiO3
Observation of an antiferromagnetic quantum critical point in high-purity LaNiO3
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DOI：
10.1038/s41467-020-15143-w
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发表时间：
2020-02
影响因子：
16.6
通讯作者：
Changjiang Liu;V. Humbert;Terence M. Bretz-Sullivan;Gensheng Wang;Deshun Hong;F. Wrobel;Jianjie Zhang;J. Hoffman;J. Pearson;J. Jiang;C. Chang;A. Suslov;N. Mason;M. Norman;A. Bhattacharya
中科院分区：
文献类型：
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作者：
Changjiang Liu;V. Humbert;Terence M. Bretz-Sullivan;Gensheng Wang;Deshun Hong;F. Wrobel;Jianjie Zhang;J. Hoffman;J. Pearson;J. Jiang;C. Chang;A. Suslov;N. Mason;M. Norman;A. Bhattacharya
在稀土钙钛矿镍酸盐中，LaNiO3（LNO）是个例外。前者具有绝缘和反铁磁基态，而LNO在最低温度下仍保持金属和非磁性。人们认为LNO是一种奇怪的金属，处于反铁磁不稳定的边缘。我们的工作表明LNO是一种量子临界金属，接近反铁磁量子临界点（QCP）。LNO中的QCP行为在外延薄膜中得到了前所未有的高纯度表现。我们发现低温下LNO电阻率的温度和磁场依赖性与弱无序和反铁磁性质的量子涨落引起的载流子散射一致。此外，我们发现少量磁性杂质的引入定性地改变了LNO的磁输运性质，类似于在反铁磁QCP附近的一些重费米子近道晶格系统中发现的情况。
Amongst the rare-earth perovskite nickelates, LaNiO3(LNO) is an exception. While the former have insulating and antiferromagnetic ground states, LNO remains metallic and non-magnetic down to the lowest temperatures. It is believed that LNO is a strange metal, on the verge of an antiferromagnetic instability. Our work suggests that LNO is a quantum critical metal, close to an antiferromagnetic quantum critical point (QCP). The QCP behavior in LNO is manifested in epitaxial thin films with unprecedented high purities. We find that the temperature and magnetic field dependences of the resistivity of LNO at low temperatures are consistent with scatterings of charge carriers from weak disorder and quantum fluctuations of an antiferromagnetic nature. Furthermore, we find that the introduction of a small concentration of magnetic impurities qualitatively changes the magnetotransport properties of LNO, resembling that found in some heavy-fermion Kondo lattice systems in the vicinity of an antiferromagnetic QCP.