Orientation control of ideal blue phase photonic crystals

AbstractControlling the crystallographic orientation of 3D photonic crystals is important as it determines the behavior of light propagating through the device. Blue phases self-assemble into unique soft 3D photonic crystals with chiral structures for circular-polarization selectivity, but it has remained a challenge to control its 3D orientation. Here, we show that the orientation of blue phases can be precisely controlled to follow a predefined pattern imprinted on a substrate by exploiting field-induced phase transitions. Obtaining the blue phase through the field-induced chiral nematic phase and tetragonal blue phase X results in a highly oriented blue phase I with the crystallographic [001] direction aligned along the surface anchoring. Our approach is applied to fabricating a Bragg-Berry hologram with omnidirectional circular-polarization selectivity, where the hologram is visible only for one circular-polarization under all incident angles. Such devices are difficult to fabricate using conventional optical materials, thereby demonstrating the potential of self-organizing soft matter for photonics.

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Fast self-assembly of macroscopic blue phase 3D photonic crystals

Optics Express ◽

10.1364/oe.393197 ◽

2020 ◽

Vol 28 (12) ◽

pp. 18202

Author(s):

Eva Otón ◽

Przemysław Morawiak ◽

Katarzyna Gaładyk ◽

José M. Otón ◽

Wiktor Piecek

Keyword(s):

Photonic Crystals ◽

Self Assembly ◽

Blue Phase

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Blue Phase Liquid Crystals with Tailored Crystal Orientation for Photonic Applications

Symmetry ◽

10.3390/sym13091584 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1584

Author(s):

SeongYong Cho ◽

Masanori Ozaki

Keyword(s):

Liquid Crystals ◽

Photonic Crystals ◽

Self Assembly ◽

Crystal Orientation ◽

Three Dimensional ◽

Optical Characteristics ◽

Crystal Plane ◽

Potential Applications ◽

Blue Phase ◽

Control Light

Blue phase (BP) liquid crystals, which self-assemble into soft three-dimensional (3D) photonic crystals, have attracted enormous research interest due to their ability to control light and potential photonic applications. BPs have long been known as optically isotropic materials, but recent works have revealed that achieving on-demand 3D orientation of BP crystals is necessary to obtain improved electro-optical performance and tailored optical characteristics. Various approaches have been proposed to precisely manipulate the crystal orientation of BPs on a substrate, through the assistance of external stimuli and directing self-assembly processes. Here, we discuss the various orientation-controlling technologies of BP crystals, with their mechanisms, advantages, drawbacks, and promising applications. This review first focuses on technologies to achieve the uniform crystal plane orientation of BPs on a substrate. Further, we review a strategy to control the azimuthal orientation of BPs along predesigned directions with a uniform crystal plane, allowing the 3D orientation to be uniquely defined on a substrate. The potential applications such as volume holograms are also discussed with their operation principle. This review provides significant advances in 3D photonic crystals and gives a huge potential for intelligent photonic devices with tailored optical characteristics.

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Tunable photonic crystals with partial bandgaps from blue phase colloidal crystals and dielectric-doped blue phases

Soft Matter ◽

10.1039/c4sm00419a ◽

2014 ◽

Vol 10 (33) ◽

pp. 6339-6346 ◽

Cited By ~ 25

Author(s):

Mitja Stimulak ◽

Miha Ravnik

Keyword(s):

Photonic Crystals ◽

Soft Matter ◽

Colloidal Crystals ◽

Photonic Material ◽

Blue Phase ◽

Blue Phases

Tunable photonic crystals from dielectric doped blue phases are demonstrated, based on the idea of combining multiple soft matter components with different symmetries into one photonic material.

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Wide-angle lasing from photonic crystal nanostructures of a liquid-crystalline blue phase

Journal of Materials Chemistry C ◽

10.1039/c9tc01350d ◽

2019 ◽

Vol 7 (21) ◽

pp. 6433-6439 ◽

Cited By ~ 1

Author(s):

Guan-Yu Zhuo ◽

Shu-Wei Huang ◽

Shih-Hung Lin

Keyword(s):

Liquid Crystals ◽

Photonic Crystal ◽

Photonic Crystals ◽

Visible Light ◽

Liquid Crystalline ◽

Wide Angle ◽

Phase Liquid ◽

Blue Phase

Wide-angle lasing emitting dye-doped blue-phase liquid crystals (DDBPLCs), which are analogous to photonic crystals, have been demonstrated to selectively reflect visible light.

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All-Optically Controllable Photonic Crystals Based on Chiral-Azobenzene-Doped Blue Phase Liquid Crystals

Crystals ◽

10.3390/cryst10100906 ◽

2020 ◽

Vol 10 (10) ◽

pp. 906

Author(s):

Shun-An Jiang ◽

Chan-Hong Wu ◽

Ting-Shan Mo ◽

Shuan-Yu Huang ◽

Jia-De Lin ◽

...

Keyword(s):

Liquid Crystals ◽

Photonic Crystals ◽

Optical Control ◽

Light Illumination ◽

Homogeneous Surface ◽

Surface Alignment ◽

All Optical ◽

Phase Liquid ◽

Blue Phase ◽

The Difference

In this study, the all-optical control properties of photonic crystals based on self-assembled chiral-azobenzene-doped blue phase liquid crystals (CA-BPLCs) were investigated. The difference in the photothermal characteristics of CA-BPLCs with and without homogeneous surface alignment was discussed. Results revealed that surface alignment could induce more uniform and diverse blue phase (BP) structures, including BPII, BPI, and BPS-like phases during cooling. Consequently, the temperature range of BP was wider than that of the sample without surface alignment. All-optical control experiments with light illumination were then performed on the aligned or nonaligned CA-BPLC samples. During continuous irradiation with light beams at wavelengths of 405 and 450 nm, CA dopants underwent trans→cis and cis→trans back photoisomerizations, respectively. These processes promoted isothermal phase transition and wavelength shifting, which further enabled the all-optical control of the CA-BPLC samples. Various optical control modes of BPLC could be achieved through phase change and wavelength shifting by appropriately selecting the working temperature and surface treatment of BPLC. This study could be further used as a basis for developing photoswitchable and tunable BPLC photonic devices, such as light-controllable gratings, filters, mirrors, and lasers.

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