  We report here and experimentally demonstrate an actively controlled
gatetunable plasmonic metasurface operating in the visible region of the
electromagnetic spectrum, where strikingly the operating voltages for
reflectance modulation are much less than 1V. The electrically tunable
metasurface consists of inverse dolmen structures (iDolmen) patterned on silver
and chromium on a quartz substrate and subsequently covered with a 5 nm thin
layer of Al2O3 followed by a 110 nm indium tin oxide (ITO) layer, which acts as
a transparent electrode. Our designed structures show up to 78 percent change
in reflection upon applying small voltages (less than 1V). We explain this
behaviour via ion conductance of silver through Al2O3 and ITO, leading to
active resistive switching. Interesting complementary effects such as decreased
reflection in the same structures over a broadband of wavelengths is also seen
on reversing the applied bias. The results provide an insight into the use of
the resistive switching for electrical control over light-matter interaction in
plasmonic metasurfaces.
