  Dielectric metasurfaces can show multi-resonant response with high Q-factors
in the visible range due to multipole coupling. This work suggests that these
collective resonances in all-dielectric metasurfaces can be modified if
adjacent to an anisotropic liquid crystal medium, opening a new path toward the
dynamic metasurface effects. Using numerical full-wave simulations and the
multipole decomposition technique for reflection and transmission coefficients
we study the influence of the surrounding anisotropic medium on the resonant
response of metasurfaces composed of disk-shaped dielectric nanoparticles.
First, we consider tuning and switching the resonances induced by the
polarization of the incident beam in metasurfaces placed in a medium with
different orientations of LC molecules. Secondly, we study the case when the
tuning of resonances is carried out by applying an external voltage that
changes the orientation of LC molecules and thereby changes the refractive
index of the surrounding medium. The results obtained demonstrate the
possibility of directly tuning the resonant response of dielectric metasurfaces
in an anisotropic environment, which is important for the development of
optical nanodevices with dynamic switching of functional modes in the visible
range.
