Fig. 2: Photoinduced transition between mesophase (M) and ferronematic phase (NF).
From: Anisotropic fluid with phototunable dielectric permittivity
a Temperature-dependent dielectric permittivity of liquid-crystalline (LC) blends ([Azo-F] = 0–8 wt%) in cis (orange plots) and trans (purple plots) states. The cis and trans states were realised by green light (GL; 525 nm) and blue light (BL; 415 nm) irradiation, respectively. b, c Phototunable permittivity range, (ε‘max − ε‘min); b and relative tunability [(ε‘max − ε‘min)/ε‘max; c of the LC blends ([Azo-F] = 1–8 wt%), where ε‘max and ε‘min are the maximum permittivity in the trans state and the minimum permittivity in the cis state, respectively, at a fixed temperature. d Temperature-dependent phase behaviours of the LC blends ([Azo-F] = 0–8 wt%) in cis and trans states. e Polarised optical microscopy images under crossed Nicols of an LC blend ([Azo-F] = 4 wt%) in cis (lower) and trans (upper) states after passing through a long path filter (λ > 550 nm) at a constant temperature [left: 45 °C (cyan symbols in (d)); middle: 52 °C (green symbols in (d)); right: 60 °C (magenta symbols in (d))]. Scale: 100 μm. f–i Two-dimensional (2D; upper) and one-dimensional (1D; lower) X-ray diffraction profiles of an LC blend ([Azo-F] = 4 wt%) under a magnetic field (b; ~0.5 T): in a trans state (60 °C; f), in a trans state (52 °C; g), in a cis state after GL irradiation (52 °C; h), and in a trans state after subsequent BL irradiation (52 °C; i). Black double arrows indicate the direction of an applied magnetic field. Red lines in the 1D profiles are the best fits.
