Cholesteric liquid crystals with helicoidal molecular architecture are known
for their ability to selectively reflect light with the wavelength that is
determined by the periodicity of molecular orientations. Here we demonstrate
that by using a cholesteric with oblique helicoidal(heliconical) structure, as
opposed to the classic right-angle helicoid, one can vary the wavelength of
selectively reflected light in a broad spectral range, from ultraviolet to
visible and infrared (360-1520 nm for the same chemical composition) by simply
adjusting the electric field applied parallel to the helicoidal axis. The
effect exists in a wide temperature range (including the room temperatures) and
thus can enable many applications that require dynamically controlled
transmission and reflection of electromagnetic waves, from energy-saving smart
windows to tunable organic lasers, reflective color display, and transparent
see-through displays.Comment: 11 pages, 5figure