Utilizing high-resolution photoemission spectroscopy (ARPES) with fine-tuned polarization selection we present a systematic study of the insulating cobaltates. A single-particle gap opening is observed, suggesting an anisotropic particle-hole instability is present due to the material's unique topology. Unlike conventional density waves, charge stripes or band insulators, the onset of the gap depends on the quasiparticle's quantum coherence, which occurs well below the symmetry breaking temperature of the crystal.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- C. Photoelectron spectroscopy
- D. Fermi surface
- D. Spin-density waves