Spin-valley coupling in single-electron bilayer graphene quantum dots

被引：53

作者：

Banszerus, L. ^{[1
,2
,3
]}

Moeller, S. ^{[1
,2
,3
]}

Steiner, C. ^{[1
,2
,3
]}

Icking, E. ^{[1
,2
,3
]}

Trellenkamp, S. ^{[4
]}

Lentz, F. ^{[4
]}

Watanabe, K. ^{[5
]}

Taniguchi, T. ^{[6
]}

Volk, C. ^{[1
,2
,3
]}

Stampfer, C. ^{[1
,2
,3
]}

机构：

[1] Rhein Westfal TH Aachen, JARA FIT, Aachen, Germany

[2] Rhein Westfal TH Aachen, Inst Phys 2, Aachen, Germany

[3] Forschungszentrum Julich, Peter Grunberg Inst PGI 9, Julich, Germany

[4] Forschungszentrum Julich, Helmholtz Nano Facil, Julich, Germany

[5] Natl Inst Mat Sci, Res Ctr Funct Mat, Tsukuba, Ibaraki, Japan

[6] Natl Inst Mat Sci, Int Ctr Mat Nanoarchitecton, Tsukuba, Ibaraki, Japan

来源：

NATURE COMMUNICATIONS | 2021年 / 12卷 / 01期

基金：

欧洲研究理事会; 欧盟地平线“2020”;

关键词：

D O I：

10.1038/s41467-021-25498-3

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Understanding how the electron spin is coupled to orbital degrees of freedom, such as a valley degree of freedom in solid-state systems, is central to applications in spin-based electronics and quantum computation. Recent developments in the preparation of electrostatically-confined quantum dots in gapped bilayer graphene (BLG) enable to study the low-energy single-electron spectra in BLG quantum dots, which is crucial for potential spin and spin-valley qubit operations. Here, we present the observation of the spin-valley coupling in bilayer graphene quantum dots in the single-electron regime. By making use of highly-tunable double quantum dot devices we achieve an energy resolution allowing us to resolve the lifting of the fourfold spin and valley degeneracy by a Kane-Mele type spin-orbit coupling of approximate to 60 mu eV. Furthermore, we find an upper limit of a potentially disorder-induced mixing of the K and K' states below 20 mu eV.

引用

页数：7

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