title: Liquid-crystal-based tunable high-Q directional random laser from a planar random microcavity.
abstract: Temperature-tunable directional laser emission from a dye-doped liquid-crystal-based planar random cavity laser is presented. The optically pumped nematic liquid crystal infiltrated planar random microcavity produces an ultranarrow linewidth (0.03 nm, corresponding to Q>20,000), highly directional (1.4 degrees divergence angle) laser emission. By increasing the temperature from 27 degrees C to 34 degrees C, the wavelength of an emitted polarized laser can be tuned between 605.8 and 608.5 (ordinary light) and 631.3 and 624.9 nm (extraordinary light). A simulation result from the transfer matrix method that matches the experimental results well is also presented.
authors.affiliation: State Key Lab for Advanced Photonic Materials and Devices, Department of Optical Science and Engineering, School of Information Science and Engineering, Fudan University, Shanghai, China.
authors.forename: Qinghai
authors.initials: Q
authors.lastname: Song
authors.forename: Shumin
authors.initials: S
authors.lastname: Xiao
authors.forename: Xinchuan
authors.initials: X
authors.lastname: Zhou
authors.forename: Liying
authors.initials: L
authors.lastname: Liu
authors.forename: Lei
authors.initials: L
authors.lastname: Xu
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Wu
authors.forename: Zhanshan
authors.initials: Z
authors.lastname: Wang