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In contrast to conventional anti‐counterfeiting technologies, which are susceptible to decryption and exhibit limited effectiveness, the utilization of light to dynamically configure soft materials in a fully reversible and programmable manner not only enhances data security but also improves anti‐counterfeiting performance. However, achieving precise control over reflection structural colors and laser wavelengths within a broad dynamic range remains a challenge. In this study, a UV‐responsive soft helical superstructure is established by combining a photochromic compound with chiral liquid crystals (LCs). By manipulating the Bragg reflection angle, structural reflection colors ranging from red to cyan are successfully achieved. The introduction of an anti‐counterfeiting technique that embeds diverse micro‐structures provides features such as color adjustability, erasability, and angle‐dependent stability. Using the unique properties of this soft helical superstructure, the implementation of a wavelength‐tunable LC bandgap laser through optically reconfigurable Förster resonance energy transfer processes is showcased. Furthermore, a straightforward prototype information encoder is developed to mimic the processes of information encoding and decoding, bypassing the need for complex algorithm design. This research underscores the practicality of LC helical soft systems, emphasizing their distinctive responsiveness to light and their applicability in optical programming photonics. [ABSTRACT FROM AUTHOR]

Liquid‐crystal random lasers (LCRLs) represent a burgeoning field in soft‐matter photonics, holding promise for ushering in an era of ultrathin, versatile laser sources. Such lasers encompass a multitude of remarkable features, including wide‐band tunability, large coherence area and, in some cases, multidirectional emission. In this paper, an LCRL is developed by doping a laser dye, pyrromethene 597 (PM597), into cholesteric LC, but achieving a wide‐range wavelength‐controllable (560–720 nm) bandgap lasing through voltage control. Bandgap lasing intriguingly occurs in media with extremely low dye gain, which is mainly contributed by the extremely high photon density of states (DOS) at the edge of the LC bandgap. In addition, the utilization rate of the fluorescence spectrum (550–750 nm) of laser dye PM597 is as high as 80%. The multivariate linear regression model is used to characterize the inherent relationship between the lasing intensity emitted by LC and the photon DOS, fluorescence quantum yield, and internal scattering under specific pumping energy. This model shows the potential to predict the critical conditions of laser emission accurately and provides the capability to design and fabricate large‐scale multifunctional responsive photonic crystals using a simple fabrication procedure. [ABSTRACT FROM AUTHOR]

Herein, polychloride ([Cl3]− or/and [Cl5]−) ionic liquids (ILs) were prepared from their imidazolium chloride precursors by the addition of chlorine gas. The highest storage ability of Cl2 was found in the [Bmim]Cl IL among the six imidazolium chlorides [Rmim]Cl (Rmim = Emim, 1-ethyl-3-methylimidazolium; Bmim, 1-butyl-3-methylimidazolium; Pmim, 1-propyl-3-methylimidazolium; Pnmim, 1-pentyl-3-methylimidazolium; Hmim, 1-hexyl-3-methylimidazolium; and Omim, 1-octyl-3-methylimidazolium). When a mixed IL of [Bmim][Tf2N] (1-butyl-3-methylimidazolium bistriflimide) and [Bmim]Cl was used, the IL cation could maintain good stability during the chlorination process, and the imidazolium cation [Bmim]+ could retain almost the same structure after the chlorine gas was introduced into the mixed IL according to 1H NMR spectroscopy. It has been found that the synthesized polychloride ILs not only can successfully dissolve UO2, but can also decrease the consumption of Cl2 and increase the chlorine efficiency. Spectroscopy studies indicate that [UO2Cl4]2− is the principal product in the IL reaction solution. The dissolved uranyl species can be easily recovered from the ILs by crystallization in the form of [Bmim]2[UO2Cl4]. Moreover, even if 57.1 wt% of the lanthanide element, when compared with the total amount of dissolved uranium and lanthanide elements, was dissolved in the IL mixture, only uranium-containing crystals could be isolated from the system. [ABSTRACT FROM AUTHOR]

Herein, polychloride ([Cl3]− or/and [Cl5]−) ionic liquids (ILs) were prepared from their imidazolium chloride precursors by the addition of chlorine gas. The highest storage ability of Cl2 was found in the [Bmim]Cl IL among the six imidazolium chlorides [Rmim]Cl (Rmim = Emim, 1-ethyl-3-methylimidazolium; Bmim, 1-butyl-3-methylimidazolium; Pmim, 1-propyl-3-methylimidazolium; Pnmim, 1-pentyl-3-methylimidazolium; Hmim, 1-hexyl-3-methylimidazolium; and Omim, 1-octyl-3-methylimidazolium). When a mixed IL of [Bmim][Tf2N] (1-butyl-3-methylimidazolium bistriflimide) and [Bmim]Cl was used, the IL cation could maintain good stability during the chlorination process, and the imidazolium cation [Bmim]+ could retain almost the same structure after the chlorine gas was introduced into the mixed IL according to 1H NMR spectroscopy. It has been found that the synthesized polychloride ILs not only can successfully dissolve UO2, but can also decrease the consumption of Cl2 and increase the chlorine efficiency. Spectroscopy studies indicate that [UO2Cl4]2− is the principal product in the IL reaction solution. The dissolved uranyl species can be easily recovered from the ILs by crystallization in the form of [Bmim]2[UO2Cl4]. Moreover, even if 57.1 wt% of the lanthanide element, when compared with the total amount of dissolved uranium and lanthanide elements, was dissolved in the IL mixture, only uranium-containing crystals could be isolated from the system. [ABSTRACT FROM AUTHOR]

The enthusiasm for research on liquid crystal random lasers (LCRLs) is driven by their unusual optical properties and promising potential for broad applications in manufacturing, communications, medicine and entertainment. From this perspective, we will summarize the most attractive advances in the development of LCRLs in the last decade and propose future prospects. This article will begin with a fundamental description of LCRLs, including the principle of laser generation and a description of LC substances. Then, we spend several chapters on the lasing performance control methods of LCRLs, including random lasing wavelength, threshold, and polarization properties. In addition, we analyze how the LC chiral agent structures, LC core-shell structures and new light-amplifying materials affect the design of LCRL devices. In the last chapter, we discuss the application of LCRLs in 3D displays, information encryption, biochemical sensing and other optoelectronics devices and finally end the perspective with LCRLs' likely directions in future research.