Shashkin A A, Melnikov M Yu, Dolgopolov V T, Radonjić M M, Dobrosavljević V, Huang S-H, Liu C W, Zhu Amy Y X, Kravchenko S V
Institute of Solid State Physics, Chernogolovka, Moscow District, 142432, Russia.
Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080, Belgrade, Serbia.
Sci Rep. 2022 Mar 24;12(1):5080. doi: 10.1038/s41598-022-09034-x.
The increase in the resistivity with decreasing temperature followed by a drop by more than one order of magnitude is observed on the metallic side near the zero-magnetic-field metal-insulator transition in a strongly interacting two-dimensional electron system in ultra-clean SiGe/Si/SiGe quantum wells. We find that the temperature [Formula: see text], at which the resistivity exhibits a maximum, is close to the renormalized Fermi temperature. However, rather than increasing along with the Fermi temperature, the value [Formula: see text] decreases appreciably for spinless electrons in spin-polarizing (parallel) magnetic fields. The observed behaviour of [Formula: see text] cannot be described by existing theories. The results indicate the spin-related origin of the effect.
在超清洁的SiGe/Si/SiGe量子阱中强相互作用二维电子系统的零磁场金属-绝缘体转变附近的金属侧，观察到电阻率随温度降低而增加，随后下降超过一个数量级。我们发现电阻率呈现最大值时的温度[公式：见正文]接近重整化费米温度。然而，对于自旋极化（平行）磁场中的无自旋电子，[公式：见正文]的值不是随费米温度升高，而是明显降低。现有理论无法描述观察到的[公式：见正文]行为。结果表明该效应源于自旋相关。
