Ultrasound evidence for multicomponent superconducting order parameter in Ba1−xKxFe2As2 with electron quadrupling phase
Source abstract
Abstract
Abstract Experiments have pointed to the formation of the electron quadrupling condensate in Ba 1− x K x Fe 2 As 2 at x ~ 0.8. The state spontaneously breaks time-reversal symmetry and is sandwiched between two critical points, separating it from the broken time-reversal symmetry (BTRS) superconducting state at $${T}_{{\rm{c}}}U(1)$$ and a normal-metal state at $${T}_{{\rm{c}}}^{{\rm{Z2}}}$$ . We report a theory of the acoustic effects spectroscopy of systems with an electron quadrupling phase based on ultrasound-velocity measurements. We show that the experimental results are consistent with BTRS superconductivity at x ~ 0.8, fulfilling the necessary condition for the formation of electron quadrupling in Ba 1− x K x Fe 2 As 2 . We provide the theoretical basis and the experimental strategy to study the order parameter symmetry of emerging quadrupling condensates in superconductors.
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Research context
OpenAlex topics: Iron-based superconductors research · Rare-earth and actinide compounds · Superconductivity in MgB2 and Alloys
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (46)
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