Fig. 2: Pseudogap spectral weight vs. temperature in optimally-doped NCCO.
From: Emergence of pseudogap from short-range spin-correlations in electron-doped cuprates
a Momentum-integrated energy distribution curves (EDCs) along the near-nodal direction (green line in Fig. 1b) for different pump-probe delays. Fermi-Dirac distribution fits are shown as solid black lines. The inset displays three delays (−0.5 ps LF, +0.33 ps HF, +2 ps HF) in logarithmic scale. b Transient electronic temperature extracted by fitting the Fermi edge broadening along the near-nodal direction (a), for both LF and HF. The solid lines are phenomenological double exponential-decay fits (decay times are: 0.6 ± 0.1 ps and 7.5 ± 1.3 ps for LF, 0.45 ± 0.15 ps and 8.3 ± 2 ps for HF). Grey points indicate time delays for which a pure thermal-fitting is not accurate (see Supplementary Discussion G). Error bars represent the confidence interval in the fitting procedure corresponding to ±3σ (σ is the standard deviation). c Temporal evolution of the photoemission intensity at the HS for ω = −50 ± 10 meV (see black line and violet dotted circle in Fig. 1b), for both the employed pump fluences LF and HF. The solid black line is a phenomenological single exponential-decay fit for the LF curve while the HF curve saturates in the first 2 ps after the pump excitation. Error bars represent ±σ. d Photoemission intensity at the HS, ω = −50 ± 10 meV, as a function of the electronic temperature (black and red circles for LF and HF, respectively; data points are plotted vs. the electronic temperature determined from the phenomenological fits in (b)). Non-thermal time delays, grey points in (b, c), have been omitted. The green line and transparent shadow represent the inverse of the spin-correlation length ξspin from neutron scattering studies for optimal doping Tc ~ 24 K,24 appropriately scaled and offset. We identify T* as the temperature at which the PG is completely filled (in agreement with the saturation of the photoemission intensity at the HS for ω = −50 ± 10 meV for HF). Error bars are defined in (b, c). Data have been replicated for three different cleaves.
