8.5 Towards Optoelectronic Devices and Microcavity Experiments with 2D Materials
239
In addition, alternative heterostructures such as the ML–ML WSe 2 /WS 2 type-II
structure are currently under investigation [110], and the use of such heterojunctions
in 2D photovoltaic devices will be explored. Also, in order to see if intersubband
transitions for few-layer TMDC [111] can be used for device concepts employing outof-plane fields for possible tunable resonance-tunnelling effects, which requires that
the Bloch wave nature perseveres under bias, cooperative work on quantum wells
made from van-der-Waals materials has been targeted together with the research
group of H. G. Roskos in Frankfurt.
Furthermore, given the strong interest in light–matter coupling experiments, the
overarching working title “2D-materials optical RESOnator NAnoTEchnologies
(2RESONATE)” was defined by the author in August 2017, with the (long-term)
aim to explore open tunable resonator concepts with 2D materials as active medium
(Fig. 8.1).
An experimental testbed for strong light–matter interactions has been in development over the last years, also in collaboration with the research group of W. Fang
in Hangzhou [112] (see Fig. 7.7), and complementary theoretical studies by the
author’s team have proposed continuously tunable light–matter coupling in microcavities with 2D materials [95] (see Figs. 3.2 and 4.8). With such, a transition from
the strong to the weak coupling regime can be investigated and the properties of such
system around the exceptional point of the light–matter coupling explored.
Moreover, it is the author’s aim to utilise piezo-driven tunable optical microcavities with low mode volume (operational at very-low and room temperature),
which incorporate suitable 2D-material systems (currently used also in the context of Purcell effect studies in the author’s team), and (ideally) with high-quality
polarisation-selective optical mirrors. These systems are targeted for polariton condensation studies at elevated temperatures up to room temperature and (ideally) for
helicity-dependent coupling effects (Fig. 8.2). Future work also aims at the exploration of 2D–nanophotonic structures with nontrivial optical topological properties.
To obtain helicity-dependent reflectivities, first efforts by the author’s team
involved nanopatterning highly-reflecting mirrors for valley-selective nanophotonics
(cf. Fig. 8.3 for an early concept, with spectra calculated using a free electromagFig. 8.1 Overview of the
goals within the frame of
“2RESONATE”
239
In addition, alternative heterostructures such as the ML–ML WSe 2 /WS 2 type-II
structure are currently under investigation [110], and the use of such heterojunctions
in 2D photovoltaic devices will be explored. Also, in order to see if intersubband
transitions for few-layer TMDC [111] can be used for device concepts employing outof-plane fields for possible tunable resonance-tunnelling effects, which requires that
the Bloch wave nature perseveres under bias, cooperative work on quantum wells
made from van-der-Waals materials has been targeted together with the research
group of H. G. Roskos in Frankfurt.
Furthermore, given the strong interest in light–matter coupling experiments, the
overarching working title “2D-materials optical RESOnator NAnoTEchnologies
(2RESONATE)” was defined by the author in August 2017, with the (long-term)
aim to explore open tunable resonator concepts with 2D materials as active medium
(Fig. 8.1).
An experimental testbed for strong light–matter interactions has been in development over the last years, also in collaboration with the research group of W. Fang
in Hangzhou [112] (see Fig. 7.7), and complementary theoretical studies by the
author’s team have proposed continuously tunable light–matter coupling in microcavities with 2D materials [95] (see Figs. 3.2 and 4.8). With such, a transition from
the strong to the weak coupling regime can be investigated and the properties of such
system around the exceptional point of the light–matter coupling explored.
Moreover, it is the author’s aim to utilise piezo-driven tunable optical microcavities with low mode volume (operational at very-low and room temperature),
which incorporate suitable 2D-material systems (currently used also in the context of Purcell effect studies in the author’s team), and (ideally) with high-quality
polarisation-selective optical mirrors. These systems are targeted for polariton condensation studies at elevated temperatures up to room temperature and (ideally) for
helicity-dependent coupling effects (Fig. 8.2). Future work also aims at the exploration of 2D–nanophotonic structures with nontrivial optical topological properties.
To obtain helicity-dependent reflectivities, first efforts by the author’s team
involved nanopatterning highly-reflecting mirrors for valley-selective nanophotonics
(cf. Fig. 8.3 for an early concept, with spectra calculated using a free electromagFig. 8.1 Overview of the
goals within the frame of
“2RESONATE”