TY - JOUR
T1 - Photonic bandgap–cholesteric device with electrical tunability and optical tristability in its defect modes
AU - Wu, Po Chang
AU - Hsiao, Chih Yuan
AU - Lee, Wei
PY - 2017/7/1
Y1 - 2017/7/1
N2 - This study proposes a hybrid structure for a one-dimensional (1D) photonic crystal (PC) comprising a tristable cholesteric liquid crystal (CLC) as the defect layer. The CLC exhibits three optically stable states: the Grandjean planar (P), focal conic (FC), and uniform lying helix (ULH) configurations. Specifically, the reflection band of the CLC is set within the photonic bandgap (PBG) of the 1D PC. While the ULH and the FC states can be regarded as the light-on and light-off states for defect-mode peaks in the visible spectrum, respectively, switching the device from the ULH to the P state enables suppression of the transmission of partial defect modes within the PBG. This device possesses many alluring features, such as optical tristability at null applied voltage and transmission tunability of the defect modes, providing a new pathway for the design of multifunctional and energy-efficient optical switches, light shutters, multichannels, and wavelength selectors.
AB - This study proposes a hybrid structure for a one-dimensional (1D) photonic crystal (PC) comprising a tristable cholesteric liquid crystal (CLC) as the defect layer. The CLC exhibits three optically stable states: the Grandjean planar (P), focal conic (FC), and uniform lying helix (ULH) configurations. Specifically, the reflection band of the CLC is set within the photonic bandgap (PBG) of the 1D PC. While the ULH and the FC states can be regarded as the light-on and light-off states for defect-mode peaks in the visible spectrum, respectively, switching the device from the ULH to the P state enables suppression of the transmission of partial defect modes within the PBG. This device possesses many alluring features, such as optical tristability at null applied voltage and transmission tunability of the defect modes, providing a new pathway for the design of multifunctional and energy-efficient optical switches, light shutters, multichannels, and wavelength selectors.
KW - Cholesteric liquid crystals
KW - Energy-efficient photonic devices
KW - Photonic crystals
UR - http://www.scopus.com/inward/record.url?scp=85021660681&partnerID=8YFLogxK
U2 - 10.3390/cryst7070184
DO - 10.3390/cryst7070184
M3 - Article
AN - SCOPUS:85021660681
VL - 7
JO - Crystals
JF - Crystals
SN - 2073-4352
IS - 7
M1 - 184
ER -