Quasi-one-dimensional pair density wave superconducting state

Abstract

We provide a quasi-one-dimensional model which can support a pair-density-wave (PDW) state, in which the superconducting (SC) order parameter modulates periodically in space, with gapless Bogoliubov quasiparticle excitations. The model consists of an array of strongly-interacting one-dimensional systems, where the one-dimensional systems are coupled to each other by local interactions and tunneling of the electrons and Cooper pairs between them. Within the interchain mean-field theory, we find several SC states from the model, including a conventional uniform SC state, PDW SC state, and a coexisting phase of the uniform SC and PDW states. In this quasi-1D regime we can treat the strong correlation physics essentially exactly using bosonization methods and the crossover to the 2D system by means of interchain mean field theory. The resulting critical temperatures of the SC phases generically exhibit a power-law scaling with the coupling constants of the array, instead of the essential singularity found in weak-coupling BCS-type theories. Electronic excitations with an open Fermi surface, which emerge from the electronic Luttinger liquid systems below their crossover temperature to the Fermi liquid, are then coupled to the SC order parameters via the proximity effect. From the Fermi surface thus coupled to the SC order parameters, we calculate the quasiparticle spectrum in detail. We show that the quasiparticle spectrum can be fully gapped or nodal in the uniform SC phase and also in the coexisting phase of the uniform SC and PDW parameters. In the pure PDW state, the excitation spectrum has a reconstructed Fermi surface in the form of Fermi pockets of Bogoliubov quasiparticles.

Holographic fermions in striped phases

“…segments and Fermi arcs appearing in PDW phases, see e.g. [21][22][23][24]. In particular, we anticipate that in the fully crystallized case (in which translational invariance is broken along all boundary directions) the Fermi surface will consist of detached pieces similar to Fermi arcs (see also the discussion of Fermi surface reconstruction in e.g.…”

Gapless Triplet Superconductivity in Magnetically Polarized Media

“…A similar TCPDWSC state channel has been suggested to occur in the high field SC state of CeCoIn 5 coexisting with singlet SC and spin density waves [18,19] explaining fascinating neutron scattering results [20]. There have also been studies of TCPDWSC in the singlet channel, also called η-pairing, [21][22][23][24][25]27] mainly motivated by the extraordinary physics in the pseudogap and other stripe regimes of cuprates [28,29] where extended FS in the SC state has been reported as well [22].…”

Superconducting and charge-density-wave orders in the spin-fermion model: A comparative analysis

“…The magnetic scenario for CDW-x order is appealing by two reasons. First, the CDW-x order between hot fermions develops together with pair-density-wave (PDW) order 11,12,[18][19][20][21][22] , and the combination of the two explains specific features of ARPES data 15,17,19,23 . Second, a Ginzburg-Landau (GL) analysis shows 12,15,16,24,25 that CDW-x order breaks not only U (1) translational symmetry, as is expected for any incommensurate charge order with a complex order parameter, but also C 4 lattice rotational symmetry and time-reversal symmetry.…”