Temperature and carrier concentration dependence of Fermi arcs in moderately underdoped Bi2Sr2CaCu2O8+δ cuprate …

Employing an autocorrelation analysis of angle resolved photoemission spectroscopy data, we have investigated the evolution of the joint density of states (JDOS) in the pseudogap phase of slightly underdoped ${\mathrm{Bi}}_{2}{\mathrm{Sr}}_{2}{\mathrm{CaCu}}_{2}{\mathrm{O}}_{8+\ensuremath{\delta}}(\mathrm{Bi}2212)$ cuprate high temperature superconductors for different temperatures $(T'\mathrm{s})$ and carrier concentrations $(\ensuremath{\delta}'\mathrm{s})$. Our JDOS analysis show that the Fermi arcs expand with increasing $T$ at a fixed $\ensuremath{\delta}$ and with increasing $\ensuremath{\delta}$ at a specific $T$. Qualitatively, these observations are consistent with the theoretical scenarios of the pseudogap phase being a phase incoherent $d$-wave superconductor, in which the Fermi arcs are described in terms of a subtle balance between temperature-dependent lifetime broadening of the single-particle excitations and the magnitude of the pairing gap.