Molecular Technology for Chirality Control: From Structure to Circular Polarization

Magnetically controllable random laser in ferromagnetic nematic liquid crystals

“…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]. However, to reorient the nematic director using a weak magnetic field, high magnetic anisotropy ∆ χ of the LC molecule is needed [23,24], which is defined as the subtraction of the molar magnetic susceptibility component ( χ ⊥ ) perpendicular to the molecular long axis from that ( χ ) parallel to the axis [25].…”