Título: Selective excitation of electrons in Fe-based systems using trARPES

Kalobaran Maiti
(Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India)

Research in material science is becoming more and more challenging due to the discovery of coexisting mutually exclusive scenarios. For example, heavy Fermion systems, Fe-based superconductors, etc. often show coexistence of magnetic order and superconductivity. Since multiple bands form the Fermi sea in these materials, it is difficult to probe the underlying interactions leading to such complexity. In order to investigate the possibility of inducing orbital selective electron dynamics, we studied the polarization-dependent excitation of electrons using time-resolved ARPES technique. We discover that electrons of a selected symmetry can be excited using polarized pump pulse keeping other electrons relatively less perturbed. Using this technique, we showed [1] that the relaxation of mobile electrons occurs faster than local electrons in contrast to the expected behavior. This can be attributed to the electron-phonon coupling induced relaxation which occurs more efficiently for the extended states. In addition, we discover melting of magnetic order at a time scale of 50 fs. Interestingly, other excitations occurring at a time scale of about 200 fs can be induced without perturbing the magnetic order.

 [1] G. Adhikary, B. Ressel, M. Stupar, P. R. Ribič, J. Urbančič, G. De Ninno, D. Krizmancic, A. Thamizhavel, and K. Maiti, Phys. Rev. B 98, 205142 (2018).
[2] G. Adhikary, T. Saha, P. R. Ribič, M. Stupar, B. Ressel, J. Urbančič, G. De Ninno, A. Thamizhavel, and K. Maiti, arXiv: 2005.01013

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ID da reunião: 439 687 5843
Senha de acesso: 660629

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