| Autor: |
Avigo, I., Thirupathaiah, S., Ligges, M., Wolf, T., Fink, J., Bovensiepen, U. |
| Rok vydání: |
2016 |
| Předmět: |
|
| Druh dokumentu: |
Working Paper |
| DOI: |
10.1088/1367-2630/18/9/093028 |
| Popis: |
Using femtosecond time- and angle-resolved photoemission spectroscopy we investigate the effect of electron doping on the electron dynamics in Ba(Fe_{1-x}Co_x)_2As_2 in a range of 0 < x < 0.15 at temperatures slightly above the N\'eel temperature. By analyzing the time-dependent photoemission intensity of the pump laser excited population as a function of energy, we found that the relaxation times at 0 < E-E_F < 0.2 eV are doping dependent and about 100 fs shorter at optimal doping than for overdoped and parent compounds. Analysis of the relaxation rates also reveals the presence of a pump fluence dependent step in the relaxation time at E-E_F = 200meV which we explain by coupling of the excited electronic system to a boson of this energy. We compare our results with static ARPES and transport measurements and find disagreement and agreement concerning the doping-dependence, respectively. We discuss the effect of the electron-boson coupling on the energy-dependent relaxation and assign the origin of the boson to a magnetic excitation. |
| Databáze: |
arXiv |
| Externí odkaz: |
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