42
2 Entering a Two-Dimensional Materials World
Fig. 2.14 Light–matter coupling experiment employing Mott–Wannier (M) excitons (X) in an inorganic 2D semiconductor simultaneously with Frenkel (F) excitons in an organic material, achieving
hybridisation of up to three modes (resulting in hybrid polaritons). A CVD-grown monolayer WS 2
flake (a) is employed on a dielectric mirror (c). Electrodes enable exciton energy tuning by lateral
electric fields. The tunable microcavity system is completed by an opposing silver mirror (top facet
of a plinth, shown in (b)). d Spectral signatures of the hybrid Frenkel–Mott polaritons obtained
with lateral bias of −210 V in transmission geometry as a function of the cavity length. a–d Reproduced under the terms of the CC-BY 4.0 Licence (http://creativecommons.org/licenses/by/4.0/).
[69] Copyright 2017 The Author(s), published by Springer Nature
examples employ strongly-confined light fields in plasmonic nanocavities with 2D
materials [67, 274].
Flexible and Tunable Coupling Experiments
With regard to flexibility in the coupling situation and a continuous tunability of the
strength of light–matter interaction around the exceptional point of the system, work
with 2D-materials–open-cavity concepts has remained promising and was further
explored in this context [275]. Recently, also fibre-tip based microcavities gained
popularity [276] which may offer new possibilities in combination with 2D materials
when it comes to low-mode-volume cavities with tunable 2D-membrane positions
[275].
Towards Valley Polaritons and Their Condensates
Particularly the domain of valley-polarisation has become a hot topic for polariton research, given access to valley-selective excitation and detection schemes and
the outlook for “optical valleytronics”. Recent reports showed pronounced circular
2 Entering a Two-Dimensional Materials World
Fig. 2.14 Light–matter coupling experiment employing Mott–Wannier (M) excitons (X) in an inorganic 2D semiconductor simultaneously with Frenkel (F) excitons in an organic material, achieving
hybridisation of up to three modes (resulting in hybrid polaritons). A CVD-grown monolayer WS 2
flake (a) is employed on a dielectric mirror (c). Electrodes enable exciton energy tuning by lateral
electric fields. The tunable microcavity system is completed by an opposing silver mirror (top facet
of a plinth, shown in (b)). d Spectral signatures of the hybrid Frenkel–Mott polaritons obtained
with lateral bias of −210 V in transmission geometry as a function of the cavity length. a–d Reproduced under the terms of the CC-BY 4.0 Licence (http://creativecommons.org/licenses/by/4.0/).
[69] Copyright 2017 The Author(s), published by Springer Nature
examples employ strongly-confined light fields in plasmonic nanocavities with 2D
materials [67, 274].
Flexible and Tunable Coupling Experiments
With regard to flexibility in the coupling situation and a continuous tunability of the
strength of light–matter interaction around the exceptional point of the system, work
with 2D-materials–open-cavity concepts has remained promising and was further
explored in this context [275]. Recently, also fibre-tip based microcavities gained
popularity [276] which may offer new possibilities in combination with 2D materials
when it comes to low-mode-volume cavities with tunable 2D-membrane positions
[275].
Towards Valley Polaritons and Their Condensates
Particularly the domain of valley-polarisation has become a hot topic for polariton research, given access to valley-selective excitation and detection schemes and
the outlook for “optical valleytronics”. Recent reports showed pronounced circular