Yim Chi Ming, Panja Soumendra Nath, Trainer Christopher, Topping Craig, Heil Christoph, Gibbs Alexandra S, Magdysyuk Oxana V, Tsurkan Vladimir, Loidl Alois, Rost Andreas W, Wahl Peter
SUPA, School of Physics and Astronomy, University of St. Andrews, North Haugh, St. Andrews, Fife KY16 9SS, U.K.
Tsung Dao Lee Institute & School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.
Nano Lett. 2021 Apr 14;21(7):2786-2792. doi: 10.1021/acs.nanolett.0c04821. Epub 2021 Apr 2.
A key property of many quantum materials is that their ground state depends sensitively on small changes of an external tuning parameter, e.g., doping, magnetic field, or pressure, creating opportunities for potential technological applications. Here, we explore tuning of the ground state of the nonsuperconducting parent compound, FeTe, of the iron chalcogenides by uniaxial strain. Iron telluride exhibits a peculiar (π, 0) antiferromagnetic order unlike the (π, π) order observed in the Fe-pnictide superconductors. The (π, 0) order is accompanied by a significant monoclinic distortion. We explore tuning of the ground state by uniaxial strain combined with low-temperature scanning tunneling microscopy. We demonstrate that, indeed under strain, the surface of FeTe undergoes a transition to a (π, π)-charge-ordered state. Comparison with transport experiments on uniaxially strained samples shows that this is a surface phase, demonstrating the opportunities afforded by 2D correlated phases stabilized near surfaces and interfaces.
许多量子材料的一个关键特性是其基态敏感地依赖于外部调谐参数（例如掺杂、磁场或压力）的微小变化，这为潜在的技术应用创造了机会。在此，我们通过单轴应变探索铁硫族化合物的非超导母体化合物FeTe基态的调谐。碲化铁呈现出奇特的(π, 0)反铁磁序，这与在铁基超导体中观察到的(π, π)序不同。(π, 0)序伴随着显著的单斜畸变。我们通过结合低温扫描隧道显微镜的单轴应变来探索基态的调谐。我们证明，在应变作用下，FeTe的表面确实会转变为(π, π)电荷有序状态。与单轴应变样品的输运实验结果比较表明，这是一个表面相，展示了在表面和界面附近稳定的二维相关相所带来的机遇。
