Please use this identifier to cite or link to this item:
http://dx.doi.org/10.25673/108804
Title: | Ultrafast coupled charge and spin dynamics in strongly correlated NiO |
Author(s): | Gillmeister, Konrad Golež, Denis Chiang, Cheng-Tien ![]() Bittner, Nikolaj Pavlyukh, Yaroslav ![]() Berakdar, Jamal ![]() Werner, Philipp Widdra, Wolf |
Issue Date: | 2020 |
Type: | Article |
Language: | English |
Abstract: | Charge excitations across an electronic band gap play an important role in opto-electronics and light harvesting. In contrast to conventional semiconductors, studies of above-band-gap photoexcitations in strongly correlated materials are still in their infancy. Here we reveal the ultrafast dynamics controlled by Hund’s physics in strongly correlated photoexcited NiO. By combining time-resolved two-photon photoemission experiments with state-of-the-art numerical calculations, an ultrafast (≲10 fs) relaxation due to Hund excitations and related photo-induced in-gap states are identified. Remarkably, the weight of these in-gap states displays long-lived coherent THz oscillations up to 2 ps at low temperature. The frequency of these oscillations corresponds to the strength of the antiferromagnetic superexchange interaction in NiO and their lifetime vanishes slightly above the Néel temperature. Numerical simulations of a two-band t-J model reveal that the THz oscillations originate from the interplay between local many-body excitations and antiferromagnetic spin correlations. |
URI: | https://opendata.uni-halle.de//handle/1981185920/110759 http://dx.doi.org/10.25673/108804 |
Open Access: | ![]() |
License: | ![]() |
Journal Title: | Nature Communications |
Publisher: | Nature Publishing Group UK |
Publisher Place: | [London] |
Volume: | 11 |
Issue: | 4095 |
Original Publication: | 10.1038/s41467-020-17925-8 |
Appears in Collections: | Open Access Publikationen der MLU |
Files in This Item:
File | Description | Size | Format | |
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s41467-020-17925-8.pdf | 1.82 MB | Adobe PDF | ![]() View/Open |