Dresden 2014 – wissenschaftliches Programm
O 80.11: Vortrag
Donnerstag, 3. April 2014, 18:30–18:45, GER 38
Ultrafast electron dynamics around the antinode in optimally doped Bi2Sr2CaCu2O8+δ — •Kerstin Hanff, Lexian Yang, Gerald Rohde, Ankatrin Stange, Petra Hein, Lutz Kipp, Michael Bauer, and Kai Rossnagel — Institute of Experimental and Applied Physics, University of Kiel, Germany
Angle-resolved photoemission spectroscopy (ARPES) has added tremendously to our understanding of the electronic and superconducting properties of the cuprates, through direct measurement of the momentum-dependent electronic structure, spectral function, and order parameter. The technique is now also frequently used in pump-probe schemes and has thus added important insights on the momentum-dependent dynamics of quasiparticles and Cooper pairs. However, due to the use of ultraviolet (UV) probe pulses only, time-resolved ARPES studies on the cuprates have so far been limited in momentum space to the nodal region of the Fermi surface. Here, we report the results of time-resolved ARPES on optimally doped Bi2Sr2CaCu2O8+δ using extreme ultraviolet radiation delivered by a high-harmonic-generation source. The higher probe photon energy of 22 eV has allowed us to study the quasiparticle relaxation dynamics in momentum-space cuts that cover the complete region from the node to the antinode. Our results reveal bi-exponential decay dynamics with distinct temperature- and momentum-dependent time constants.