Degenerate plaquette physics as key ingredient of high-temperature superconductivity in cuprates
(2022) In npj Quantum Materials 7(1).- Abstract
We study the physics of high-temperature cuprate superconductors starting from the highly degenerate four-site plaquette of the t− t′− U Hubbard model as a reference system. The degeneracy causes strong fluctuations when a lattice of plaquettes is constructed. We show that there is a large binding energy between holes when a set of four plaquettes is considered. The next-nearest-neighbour hopping t′ plays a crucial role in the formation of these strongly bound electronic bipolarons whose coherence at lower temperature could be the explanation for superconductivity. A complementary approach is cluster dual fermion starting from a single degenerate plaquette, which contains the relevant short-ranged fluctuations from... (More)
We study the physics of high-temperature cuprate superconductors starting from the highly degenerate four-site plaquette of the t− t′− U Hubbard model as a reference system. The degeneracy causes strong fluctuations when a lattice of plaquettes is constructed. We show that there is a large binding energy between holes when a set of four plaquettes is considered. The next-nearest-neighbour hopping t′ plays a crucial role in the formation of these strongly bound electronic bipolarons whose coherence at lower temperature could be the explanation for superconductivity. A complementary approach is cluster dual fermion starting from a single degenerate plaquette, which contains the relevant short-ranged fluctuations from the beginning. It gives d-wave superconductivity as the leading instability under a reasonably broad range of parameters. The origin of the pseudogap is also discussed in terms of the coupling of degenerate plaquettes. Thus, some of the essential elements of cuprate superconductivity appear from the local plaquette physics.
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- author
- Danilov, Michael ; van Loon, Erik G.C.P. LU ; Brener, Sergey ; Iskakov, Sergei ; Katsnelson, Mikhail I. and Lichtenstein, Alexander I.
- organization
- publishing date
- 2022
- type
- Contribution to journal
- publication status
- published
- subject
- in
- npj Quantum Materials
- volume
- 7
- issue
- 1
- article number
- 50
- publisher
- Nature Publishing Group
- external identifiers
-
- scopus:85128891799
- ISSN
- 2397-4648
- DOI
- 10.1038/s41535-022-00454-6
- language
- English
- LU publication?
- yes
- id
- 984fa376-4039-4500-8c21-e4bceef49f4a
- date added to LUP
- 2022-07-01 13:38:52
- date last changed
- 2022-07-01 13:38:52
@article{984fa376-4039-4500-8c21-e4bceef49f4a, abstract = {{<p>We study the physics of high-temperature cuprate superconductors starting from the highly degenerate four-site plaquette of the t− t<sup>′</sup>− U Hubbard model as a reference system. The degeneracy causes strong fluctuations when a lattice of plaquettes is constructed. We show that there is a large binding energy between holes when a set of four plaquettes is considered. The next-nearest-neighbour hopping t<sup>′</sup> plays a crucial role in the formation of these strongly bound electronic bipolarons whose coherence at lower temperature could be the explanation for superconductivity. A complementary approach is cluster dual fermion starting from a single degenerate plaquette, which contains the relevant short-ranged fluctuations from the beginning. It gives d-wave superconductivity as the leading instability under a reasonably broad range of parameters. The origin of the pseudogap is also discussed in terms of the coupling of degenerate plaquettes. Thus, some of the essential elements of cuprate superconductivity appear from the local plaquette physics.</p>}}, author = {{Danilov, Michael and van Loon, Erik G.C.P. and Brener, Sergey and Iskakov, Sergei and Katsnelson, Mikhail I. and Lichtenstein, Alexander I.}}, issn = {{2397-4648}}, language = {{eng}}, number = {{1}}, publisher = {{Nature Publishing Group}}, series = {{npj Quantum Materials}}, title = {{Degenerate plaquette physics as key ingredient of high-temperature superconductivity in cuprates}}, url = {{http://dx.doi.org/10.1038/s41535-022-00454-6}}, doi = {{10.1038/s41535-022-00454-6}}, volume = {{7}}, year = {{2022}}, }