Manipulation of Polarized Random Lasers from Dye-Doped Twisted Nematic Liquid Crystals Within Wedge Cells

Magnetically controllable random laser in ferromagnetic nematic liquid crystals

“…At the bulk layer in our sample, the random laser polarization is along the local nematic director whose direction is the same as the magnetic field and emitted without being rotated as shown in Fig. 7(b) because the local nematic director is not twisted as previously explained the random laser action in twisted nematic liquid crystals [15,21]. In this way, the random laser polarization for vDFNLC was parallel to the magnetic field direction.…”

“…Because the laser action is correlated with the orientational direction of liquid crystals [15], it could respond to the molecular reorientation by a variety of external stimuli. In fact, the wavelength, intensity and polarization of the random laser in NLCs can be controlled by electrical [16][17][18][19], thermal [13,20] and magnetic [19] stimuli, and the alignment of LC cells [15,21]. In particular, the optical switching owing to the molecular reorientation in a magnetic field [22] has some advantages in remote operability [8].…”

Energy test of an efficient random laser emission collecting system

“…Random lasers (RLs) are attractive radiation sources for several applications, such as optical sensors, high-definition speckle-free imaging, lithography, holographic laser displays, etc. [1][2][3] Many materials, such as colloidal dye solutions, solid-state dyes, polymers, crystal powders, etc., have been tested as RL sources, [4][5][6][7][8][9] showing very varied energy efficiencies, pulse widths, and emission spectra ranges.…”

Random lasing action generation in polymer nanofiber with small diameters

“…Instead of a strict optical resonant cavity that is required for the conventional laser, the RL is achieved by multiple scatterings in gain media [2]. In recent years, some new scattering systems including semiconductors [3,4], biological materials [5][6][7], core-shells [8][9][10], liquid crystals [11][12][13][14], perovskites [15], noble metals [16][17][18][19], and optical fibers [20,21] were developed to achieve RLs. Numerous theor etical approaches [22][23][24][25] combined with experimental [26][27][28][29] methods had been conducted to explain the behavior and tune the performance of RL.…”