Band-selective gap opening by a C ₄-symmetric order in a proximity-coupled heterostructure Sr₂VO₃FeAs.

ABSTRACT: Complex electronic phases in strongly correlated electron systems are manifested by broken symmetries in the low-energy electronic states. Some mysterious phases, however, exhibit intriguing energy gap opening without an apparent signature of symmetry breaking (e.g., high-T_C cuprates and heavy fermion superconductors). Here, we report an unconventional gap opening in a heterostructured, iron-based superconductor Sr₂VO₃FeAs across a phase transition at T ₀ ∼150 K. Using angle-resolved photoemission spectroscopy, we identify that a fully isotropic gap opens selectively on one of the Fermi surfaces with finite warping along the interlayer direction. This band selectivity is incompatible with conventional gap opening mechanisms associat

SUBMITTER: Kim S 

PROVIDER: S-EPMC8617490 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature