%0 Journal Article %1 dong2023observation %A Dong, Shuo %A Beaulieu, Samuel %A Selig, Malte %A Rosenzweig, Philipp %A Christiansen, Dominik %A Pincelli, Tommaso %A Dendzik, Maciej %A Ziegler, Jonas D. %A Maklar, Julian %A Xian, R. Patrick %A Neef, Alexander %A Mohammed, Avaise %A Schulz, Armin %A Stadler, Mona %A Jetter, Michael %A Michler, Peter %A Taniguchi, Takashi %A Watanabe, Kenji %A Takagi, Hidenori %A Starke, Ulrich %A Chernikov, Alexey %A Wolf, Martin %A Nakamura, Hiro %A Knorr, Andreas %A Rettig, Laurenz %A Ernstorfer, Ralph %D 2023 %J Nat. Commun %K c %N 1 %P 5057-- %R 10.1038/s41467-023-40815-8 %T Observation of ultrafast interfacial Meitner-Auger energy transfer in a van der Waals heterostructure %U https://doi.org/10.1038/s41467-023-40815-8 %V 14 %X Atomically thin layered van der Waals heterostructures feature exotic and emergent optoelectronic properties. With growing interest in these novel quantum materials, the microscopic understanding of fundamental interfacial coupling mechanisms is of capital importance. Here, using multidimensional photoemission spectroscopy, we provide a layer- and momentum-resolved view on ultrafast interlayer electron and energy transfer in a monolayer-WSe2/graphene heterostructure. Depending on the nature of the optically prepared state, we find the different dominating transfer mechanisms: while electron injection from graphene to WSe2 is observed after photoexcitation of quasi-free hot carriers in the graphene layer, we establish an interfacial Meitner-Auger energy transfer process following the excitation of excitons in WSe2. By analysing the time-energy-momentum distributions of excited-state carriers with a rate-equation model, we distinguish these two types of interfacial dynamics and identify the ultrafast conversion of excitons in WSe2 to valence band transitions in graphene. Microscopic calculations find interfacial dipole-monopole coupling underlying the Meitner-Auger energy transfer to dominate over conventional Förster- and Dexter-type interactions, in agreement with the experimental observations. The energy transfer mechanism revealed here might enable new hot-carrier-based device concepts with van der Waals heterostructures.

@article{dong2023observation, abstract = {Atomically thin layered van der Waals heterostructures feature exotic and emergent optoelectronic properties. With growing interest in these novel quantum materials, the microscopic understanding of fundamental interfacial coupling mechanisms is of capital importance. Here, using multidimensional photoemission spectroscopy, we provide a layer- and momentum-resolved view on ultrafast interlayer electron and energy transfer in a monolayer-WSe2/graphene heterostructure. Depending on the nature of the optically prepared state, we find the different dominating transfer mechanisms: while electron injection from graphene to WSe2 is observed after photoexcitation of quasi-free hot carriers in the graphene layer, we establish an interfacial Meitner-Auger energy transfer process following the excitation of excitons in WSe2. By analysing the time-energy-momentum distributions of excited-state carriers with a rate-equation model, we distinguish these two types of interfacial dynamics and identify the ultrafast conversion of excitons in WSe2 to valence band transitions in graphene. Microscopic calculations find interfacial dipole-monopole coupling underlying the Meitner-Auger energy transfer to dominate over conventional Förster- and Dexter-type interactions, in agreement with the experimental observations. The energy transfer mechanism revealed here might enable new hot-carrier-based device concepts with van der Waals heterostructures.}, added-at = {2023-11-22T18:40:32.000+0100}, author = {Dong, Shuo and Beaulieu, Samuel and Selig, Malte and Rosenzweig, Philipp and Christiansen, Dominik and Pincelli, Tommaso and Dendzik, Maciej and Ziegler, Jonas D. and Maklar, Julian and Xian, R. Patrick and Neef, Alexander and Mohammed, Avaise and Schulz, Armin and Stadler, Mona and Jetter, Michael and Michler, Peter and Taniguchi, Takashi and Watanabe, Kenji and Takagi, Hidenori and Starke, Ulrich and Chernikov, Alexey and Wolf, Martin and Nakamura, Hiro and Knorr, Andreas and Rettig, Laurenz and Ernstorfer, Ralph}, biburl = {https://www.bibsonomy.org/bibtex/20679b816a74e038f0d3538128b5e7534/ctqmat}, day = 19, doi = {10.1038/s41467-023-40815-8}, interhash = {eacc83658f327a099fb94dc4b8bc2553}, intrahash = {0679b816a74e038f0d3538128b5e7534}, issn = {20411723}, journal = {Nat. Commun}, keywords = {c}, month = {08}, number = 1, pages = {5057--}, refid = {Dong2023}, timestamp = {2023-11-22T18:40:32.000+0100}, title = {Observation of ultrafast interfacial Meitner-Auger energy transfer in a van der Waals heterostructure}, url = {https://doi.org/10.1038/s41467-023-40815-8}, volume = 14, year = 2023 }