Ultrafast dynamics in the presence of antiferromagnetic correlations in electron doped cuprate La2 xCexCuO4±δ Vishik, Inna Mahmood, Fahad Alpichshev, Zhanybek ; https://orcid.org/0000-0002-7183-5203 Gedik, Nuh Higgins, Joshu Greene, Richard We used femtosecond optical pump-probe spectroscopy to study the photoinduced change in reflectivity of thin films of the electron-doped cuprate La2-xCexCuO4 (LCCO) with dopings of x=0.08 (underdoped) and x=0.11 (optimally doped). Above Tc, we observe fluence-dependent relaxation rates that begin at a temperature similar to the one where transport measurements first show signatures of antiferromagnetic correlations. Upon suppressing superconductivity with a magnetic field, it is found that the fluence and temperature dependence of relaxation rates are consistent with bimolecular recombination of electrons and holes across a gap (2ΔAF) originating from antiferromagnetic correlations which comprise the pseudogap in electron-doped cuprates. This can be used to learn about coupling between electrons and high-energy (ω&gt;2ΔAF) excitations in these compounds and set limits on the time scales on which antiferromagnetic correlations are static. American Physical Society 2017 info:eu-repo/semantics/article doc-type:article text http://purl.org/coar/resource_type/c_2df8fbb1 https://research-explorer.ista.ac.at/record/392 Vishik I, Mahmood F, Alpichshev Z, Gedik N, Higgins J, Greene R. Ultrafast dynamics in the presence of antiferromagnetic correlations in electron doped cuprate La2 xCexCuO4±δ. <i>Physical Review B</i>. 2017;95(11). doi:<a href="https://doi.org/10.1103/PhysRevB.95.115125">10.1103/PhysRevB.95.115125</a> eng info:eu-repo/semantics/altIdentifier/doi/10.1103/PhysRevB.95.115125 info:eu-repo/semantics/altIdentifier/e-issn/2469-9969 info:eu-repo/semantics/altIdentifier/issn-l/2469-9950 info:eu-repo/semantics/altIdentifier/arxiv/1601.06694 info:eu-repo/semantics/openAccess