Spatially and electrically tunable random lasing based on a polymer-stabilised blue phase liquid crystal-wedged cell

ABSTRACT

We demonstrate a spatially and electrically tunable random lasing based on polymer-stabilized blue phase liquid crystal (PS-BPLC)-wedged cell. The spatially tunable random lasers can be obtained from the laser dye-doped PS-BPLC-wedged cell through changing the pump positions, where the emission wavelength of the random laser can be tuned due to the thickness gradient of the wedged cell, which affects the scattering mean free path. Additionally, applying different electric fields can also tune the laser emission wavelength. The changing of refractive index due to the Kerr effect leads to a change in the scattering mean free path, resulting in shift of lasing wavelength. This PS-BPLC-wedged cell device has a great potential in applications of speckle-free imaging, document coding, biomedicine and other photonic devices.

POM images of gradient-pitched PS-BPLC-wedged cell at different positions of (a) x=0 mm; (b) x=1 mm; (c) x=2 mm; (d) x=3 mm; (e) x=4 mm; (f) x=5 mm; (g) x=6 mm; (h) x=7 mm; (i) x=8 mm. The scale bar is 50 μm.

KEYWORDS:

• Liquid crystal
• blue phase
• random lasing
• polymer
• tunable

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work is supported by National Natural Science Foundation of China (NSFC) [61875081], Shenzhen Science and Technology Innovation Commission [JCYJ20180305180700747, and JCYJ20160226192528793].