Chiral superconductivity from repulsive interactions in doped graphene

By R. Nandkishore, L. Levitov, A. Chubukov. Nature Physics, 2011

571 citations recorded by the source corpus.

Chiral superconductivity, which breaks time-reversal symmetry, can exhibit a wealth of fascinating properties that are highly sought after for nanoscience applications. We identify doped graphene monolayer as a system where chiral superconductivity can be realized. In this material, a unique situation arises at a doping where the Fermi surface is nested and the density of states is singular. In this regime, d-wave superconductivity can emerge from repulsive electron–electron interactions. Using a renormalization group method, we argue that superconductivity dominates over all competing orders for generic weak repulsive interactions. Superconductivity develops simultaneously in two degenerate d-wave pairing channels. We argue that the resulting superconducting state is of chiral type, with the phase of the superconducting order parameter winding by 4π around the Fermi surface. Realization of this state in doped graphene will prove that superconductivity can emerge from electron–electron repulsion, and will open the door to applications of chiral superconductivity. Chiral superconducting states are expected to support a variety of exotic and potentially useful phenomena. Theoretical analysis suggests that just such a state could emerge in a doped graphene monolayer.

Subfields: Atomic and Molecular Physics, and Optics, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/333aed164aaefebd042a5b3d02cd61094b40641a

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Atomic and Molecular Physics, and Optics

1. Ashvin Vishwanath
2. Y. Ando
3. Masatoshi Sato
4. T. Senthil
5. Hsin Lin
6. Arun Bansil
7. Liang Fu
8. Tanmoy Das

In Materials Chemistry

1. Ashvin Vishwanath
2. Y. Ando
3. Masatoshi Sato
4. Hsin Lin
5. Arun Bansil
6. Tanmoy Das
7. T. Senthil
8. Liang Fu

Citations in the corpus

• Electronic instabilities of kagome metals: Saddle points and Landau theory (2021, methodology): “In particular, the q = 4 Potts model is equivalent to the Ashkin-Teller model, and has known critical exponents with logarithmic corrections due to marginal operators (see e.g. Ref.”
• Colloquium : Topological band theory (2016, background): “Chiral superconductivity has been predicted in Sr2RuO4 (Mackenzie and Maeno 2003), doped graphene (Pathak, Shenoy, and Baskaran 2010); Nandkishore, Levitov, and Chubukov 2012), and other systems.”
• General Theory of Josephson Diodes (2021, background): “Normally, T breaking SC can happen as an instability driven by multiple order competition and correlation, like the d + id SC in 1/4 doped graphene [76, 77] and the d + is SC when a d-wave SC coexists with an s-wave SC [78–80].”
• Novel effects of strains in graphene and other two dimensional materials (2015, background): “For instance, a particularly appealing scenario occurs when graphene is doped up to the van Hove singularity, where the divergent density of states makes it prone to a number of interesting weak coupling instabilities including d-wave superconductivity [110, 207, 233, 235, 251, 347].”
• Topological superconductors: a review (2016, background): “It has been proposed [252] that chiral d-wave superconductivity with a dx2−y2±idxy gap structure may be realized if mono-layer graphene is heavily doped to the vicinity of van Hove singularity, which lies at the doping level of ±1/8 from the pristine half-filled level.”
• Origin of Mott Insulating Behavior and Superconductivity in Twisted Bilayer Graphene (2018, background): “Other properties related to this state are also discussed in the literature [49,50].”