8–12 Jul 2018
The Prince Hakone Lake Ashinoko
Asia/Tokyo timezone

Cavity-control of bright and dark interlayer excitons in van der Waals heterostructures

9 Jul 2018, 17:00
2h
The Prince Hakone Lake Ashinoko

The Prince Hakone Lake Ashinoko

144 Motohakone, Hakone-machi, Ashigara-shimo-gun Kanagawa, 250-0592 Japan

Speaker

Mr Michael Förg (Ludwig-Maximilians-Universität Munich)

Description

Monolayer transition metal dichalcogenides integrated in optical microcavities host exciton-polaritons as a hallmark of the strong light-matter coupling regime [1]. Analogous concepts for hybrid light-matter systems employing spatially indirect excitons with a permanent electric dipole moment in heterobilayer crystals promise realizations of exciton-polariton gases and condensates with immanent dipolar interactions. Here, we identify optical signatures of spatially indirect momentum-bright and momentum-dark interlayer excitons in vertical MoSe$_2$-WSe$_2$ heterostructures and implement cavity-control of both exciton manifolds. To this end we employ a tunable open-access cavity with one curved fiber-based mirror [2] and one planar mirror with extended MoSe$_2$-WSe$_2$ heterobilayer flakes on top. The configuration of controlled intermirror spacing and lateral scanning capabilities is used to explore the light-matter coupling of excitons as a function of the cavity length at representative positions of heterobilayers selected by two-dimensional cavity imaging. Our experiments quantify the strength of interlayer excitons and demonstrate Purcell enhancement in cavity-modified photonic environments [3].

[1] X. Liu, T. Galfsky, Z. Sun, F. Xia, E.-c. Lin, Y.-H. Lee, S. Kena-Cohen, and V. M. Menon, Nature Photonics 9, 30 (2015).
[2] D. Hunger, T. Steinmetz, Y. Colombe, C. Deutsch, T. W. Hänsch, and J. Reichel, New J. Phys. 12,065038 (2010).
[3] M. Förg, L. Colombier, R. Patel, J. Lindlau, A. D. Mohite, H. Yamaguchi, D. Hunger, and A. Högele, arXiv:1710.00990 (2017).

Primary author

Mr Michael Förg (Ludwig-Maximilians-Universität Munich)

Co-authors

Mr Léo Colombier (Ludwig-Maximilians-Universität Munich) Mr Robin K. Patel (Ludwig-Maximilians-Universität Munich) Ms Jessica Lindlau (Ludwig-Maximilians-Universität Munich) Mr Aditya D. Mohite (Los Alamos National Laboratory) Mr Hisato Yamaguchi (Los Alamos National Laboratory) Prof. David Hunger (Karlsruher Institut für Technologie) Alexander Högele (Fakultät für Physik, Munich Quantum Center, and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, 80539 München, Germany)

Presentation materials