Nematic superconductivity stabilized by density wave fluctuations: Possible application to twisted bilayer graphene

被引：80

作者：

Kozii, Vladyslav ^{[1
]}

Isobe, Hiroki ^{[1
]}

Venderbos, Jorn W. F. ^{[2
,3
]}

Fu, Liang ^{[1
]}

机构：

[1] MIT, Dept Phys, Cambridge, MA 02139 USA

[2] Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA

[3] Univ Penn, Dept Chem, Philadelphia, PA 19104 USA

来源：

PHYSICAL REVIEW B | 2019年 / 99卷 / 14期

基金：

美国国家科学基金会;

关键词：

ORDER;

D O I：

10.1103/PhysRevB.99.144507

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Nematic superconductors possess unconventional superconducting order parameters that spontaneously break rotational symmetry of the underlying crystal. In this work we propose a mechanism for nematic superconductivity stabilized by strong density wave fluctuations in two dimensions. While the weak-coupling theory finds the fully gapped chiral state to be energetically stable, we show that strong density wave fluctuations result in an additional contribution to the free energy of a superconductor with multicomponent order parameters, which generally favors nematic superconductivity. Our theory sheds light on the recent observation of rotational symmetry breaking in the superconducting state of twisted bilayer graphene.

引用

页数：15

共 66 条

[1] ANISOTROPIC SUPERFLUIDITY IN HE-3 - POSSIBLE INTERPRETATION OF ITS STABILITY AS A SPIN-FLUCTUATION EFFECT [J].