%0 Journal Article %1 Messerschmidt_2020 %A Messerschmidt, Simon %A Krampf, Andreas %A Vittadello, Laura %A Imlau, Mirco %A Nörenberg, Tobias %A Eng, Lukas M. %A Emin, David %D 2020 %I MDPI AG %J Crystals %K a c %N 9 %P 809 %R 10.3390/cryst10090809 %T Small-polaron hopping and low-temperature (45-225 K) photo-induced transient absorption in magnesium-doped lithium niobate %U https://doi.org/10.3390%2Fcryst10090809 %V 10 %X A strongly temperature-dependent photo-induced transient absorption is measured in 6.5mol% magnesium-doped lithium niobate at temperatures ranging from 45K to 225K. This phenomenon is interpreted as resulting from the generation and subsequent recombination of oppositely charged small polarons. Initial two-photon absorptions generate separated oppositely charged small polarons. The existence of these small polarons is monitored by the presence of their characteristic absorption. The strongly temperature-dependent decay of this absorption occurs as series of thermally assisted hops of small polarons that facilitate their merger and ultimate recombination. Our measurements span the high-temperature regime, where small-polaron jump rates are Arrhenius and strongly dependent on temperature, and the intermediate-temperature regime, where small-polaron jump rates are non-Arrhenius and weakly dependent on temperature. Distinctively, this model provides a good representation of our data with reasonable values of its two parameters: Arrhenius small-polaron hopping’s activation energy and the material’s characteristic phonon frequency.

@article{Messerschmidt_2020, abstract = {A strongly temperature-dependent photo-induced transient absorption is measured in 6.5mol% magnesium-doped lithium niobate at temperatures ranging from 45K to 225K. This phenomenon is interpreted as resulting from the generation and subsequent recombination of oppositely charged small polarons. Initial two-photon absorptions generate separated oppositely charged small polarons. The existence of these small polarons is monitored by the presence of their characteristic absorption. The strongly temperature-dependent decay of this absorption occurs as series of thermally assisted hops of small polarons that facilitate their merger and ultimate recombination. Our measurements span the high-temperature regime, where small-polaron jump rates are Arrhenius and strongly dependent on temperature, and the intermediate-temperature regime, where small-polaron jump rates are non-Arrhenius and weakly dependent on temperature. Distinctively, this model provides a good representation of our data with reasonable values of its two parameters: Arrhenius small-polaron hopping’s activation energy and the material’s characteristic phonon frequency. }, added-at = {2021-02-23T11:10:56.000+0100}, author = {Messerschmidt, Simon and Krampf, Andreas and Vittadello, Laura and Imlau, Mirco and Nörenberg, Tobias and Eng, Lukas M. and Emin, David}, biburl = {https://www.bibsonomy.org/bibtex/2c4148bc68df7f8d74f9fdd10c8310f8b/ctqmat}, day = 14, description = {Crystals | Free Full-Text | Small-Polaron Hopping and Low-Temperature (45–225 K) Photo-Induced Transient Absorption in Magnesium-Doped Lithium Niobate}, doi = {10.3390/cryst10090809}, interhash = {d5da1a4b43402b7dbcb5fdeb04d07b29}, intrahash = {c4148bc68df7f8d74f9fdd10c8310f8b}, journal = {Crystals}, keywords = {a c}, month = {09}, number = 9, pages = 809, publisher = {MDPI AG}, timestamp = {2023-10-17T11:13:08.000+0200}, title = {Small-polaron hopping and low-temperature (45-225 K) photo-induced transient absorption in magnesium-doped lithium niobate}, url = {https://doi.org/10.3390%2Fcryst10090809}, volume = 10, year = 2020 }