In situ monitoring of disorder evolution in electroinduced liquid crystal laser systems using RSB

Replica symmetry breaking (RSB) is a unique phase transition describing the transition from the paramagnetic state to the spin-glass state in magnetic systems. This study reveals the mechanism of the electric field-modulated evolution of the helical structure of cholesteric liquid crystals (CLC) and its influence on the behavior of RSB in bandgap lasers. An anisotropic shift in the helical structure of the CLC molecule is induced by applying an external electric field (0–25 V), which leads to a dynamic displacement of the CLC photonic bandgap position. This results in the progressive blue-shifting and eventual disappearance of the shorter wavelength lasing peak (∼640 nm at 0 V), while the dominant long-wavelength bandgap lasing shifts continuously from 710 to 600 nm. In addition, there is a strong correlation between the behavior of the RSB and the degree of disorder of the system during the voltage-induced phase transition of the CLCs. This correlation property provides a new method to quantitatively characterize the disorder evolution of complex photonic systems using RSB. In situ monitoring of the disorder dynamics of liquid crystal lasers is successfully achieved by establishing the correspondence between the voltage-RSB eigen spectra. The discovery lays a theoretical foundation for the development of photonic modulation devices based on soft matter phase transitions.