Related Experiment Video
Updated: Jan 24, 2026

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Symmetric Continuously Tunable Photonic Band Gaps in Blue-Phase Liquid Crystals Switched by an Alternating Current
Xiao-Wei Du1, De-Shan Hou1, Xuan Li1
1Department of Applied Physics , Hebei University of Technology , Tianjin 300401 , China.
Abstract:
Symmetric continuously tunable three-dimensional (3D) liquid photonic crystals have been investigated using self-organized blue-phase liquid crystal films. The photonic band gap in the overall visible spectrum can be tuned continuously, reversibly, and rapidly as the applied electric field changes. After driven by the applied field, four-time enhancement of the reflectivity results in more vivid reflection colors. A lasing emission of tuning working wavelength has been demonstrated by using the dye-doped blue-phase liquid crystal film. With the advantages of fast response speed, no alignment layer, large-scale electrically shift of the photonic band gap, and macro optical isotropy, this self-assembled soft material has many potential applications in high-performance reflective full-color display, 3D tunable lasers, and nonlinear optics.
Related Concept Videos
Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
Band Theory
The energy difference between these bands is known as the band gap.
Conductor, Semiconductor,...
Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Electric Field of a Continuous Line Charge
In calculations of electric fields, symmetry is of great use. For example, while calculating electric fields of continuous charge distributions.
Consider a line element with a...
Magnetic Field Of A Current Loop
Force On A Current Loop In A Magnetic Field

