Hurand S, Jouan A, Feuillet-Palma C, Singh G, Biscaras J, Lesne E, Reyren N, Barthélémy A, Bibes M, Villegas J E, Ulysse C, Lafosse X, Pannetier-Lecoeur M, Caprara S, Grilli M, Lesueur J, Bergeal N
Laboratoire de Physique et d'Etude des Matériaux -CNRS-ESPCI ParisTech-UPMC, PSL Research University, 10 Rue Vauquelin, 75005 Paris, France.
Unité Mixte de Physique CNRS-Thales, 1 Av. A. Fresnel, 91767 Palaiseau, France.
Sci Rep. 2015 Aug 5;5:12751. doi: 10.1038/srep12751.
The recent development in the fabrication of artificial oxide heterostructures opens new avenues in the field of quantum materials by enabling the manipulation of the charge, spin and orbital degrees of freedom. In this context, the discovery of two-dimensional electron gases (2-DEGs) at LaAlO3/SrTiO3 interfaces, which exhibit both superconductivity and strong Rashba spin-orbit coupling (SOC), represents a major breakthrough. Here, we report on the realisation of a field-effect LaAlO3/SrTiO3 device, whose physical properties, including superconductivity and SOC, can be tuned over a wide range by a top-gate voltage. We derive a phase diagram, which emphasises a field-effect-induced superconductor-to-insulator quantum phase transition. Magneto-transport measurements show that the Rashba coupling constant increases linearly with the interfacial electric field. Our results pave the way for the realisation of mesoscopic devices, where these two properties can be manipulated on a local scale by means of top-gates.
人工氧化物异质结构制造技术的最新进展,通过实现对电荷、自旋和轨道自由度的操控,为量子材料领域开辟了新途径。在此背景下,在LaAlO3/SrTiO3界面发现二维电子气(2-DEG),其兼具超导性和强Rashba自旋轨道耦合(SOC),是一项重大突破。在此,我们报道了一种场效应LaAlO3/SrTiO3器件的实现,其物理性质,包括超导性和SOC,可通过顶栅电压在很宽范围内进行调控。我们得出了一个相图,该相图强调了场效应诱导的超导体-绝缘体量子相变。磁输运测量表明,Rashba耦合常数随界面电场线性增加。我们的结果为实现介观器件铺平了道路,在这种器件中,这两种性质可通过顶栅在局部尺度上进行操控。