Spectroscopic evidence of low-energy gaps persisting up to 120 K in surface-doped p-terphenyl crystals
Using high-resolution photoemission spectroscopy on <em>in situ</em> potassium surface-doped <em>para</em>-terphenyl crystals, we uncover a low-energy spectral gap of 12 meV. This spectral gap displays a strong temperature-dependent gap-filling behavior and persists up to 120 K, which is consistent with the onset temperature of a weak steplike diamagnetic transition found in this material. Among a few potential candidates for the origin of the observed gaps, we argue that electron pairing is a plausible origin-a possibility consistent with fluctuating Cooper pairs forming near 120 K.
|Year of Publication||
Physical Review B