Spatially band-tunable color-cone lasing emission in a dye-doped cholesteric liquid crystal with a photoisomerizable chiral dopant.
This study investigates a spatially band-tunable color-cone lasing emission (CCLE) based on a dye-doped cholesteric liquid crystal with a photoisomerizable chiral dopant (IBM). Experimental results show that the lasing band of the formed CCLE of the cell with a photoinduced pitch gradient can be spatially tuned among various color regions by adjusting the pumped position of the cell. The spatially band tunability of the laser results from the UV-irradiation-induced decrease of the helical twisting power of IBM via trans-->cis isomerization, accordingly shrinking the pitch of the cholesteric-liquid-crystal host. The total spatially tunable wavelength range for the laser exceeds 100 nm.
Lee
C-R
CR
Institute of Electro-Optical Science and Engineering and Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan, Taiwan 701. crlee@mail.ncku.edu.tw
Lin
S-H
SH
Ku
H-S
HS
Liu
J-H
JH
Yang
P-C
PC
Huang
C-Y
CY
Yeh
H-C
HC
Ji
T-D
TD
Lin
C-H
CH