NSF-EC: Tunable Mirrorless Lasing in Cholesteric Liquid Crystalline Elastomers

NSF-EC：胆甾型液晶弹性体中的可调谐无镜激光

• 批准号: 0132611
• 负责人: Peter Palffy-Muhoray
• 金额: $ 48万
• 依托单位: Kent State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-06-01 至 2006-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0132611&HistoricalAwards=false
• 关键词: NSF; EC; Tunable; Mirrorless; Lasing

Liquid crystalline elastomers are a new class of soft materials, distinguished by the coupling between orientational order and strain, whose mechanical deformations give rise to changes in the dielectric tensor. Cholesteric liquid crystal elastomers, due to their periodic structure, are photonic band-gap materials whose band structure can be altered by mechanical strain. Optically pumped cholesteric liquid crystal elastomers exhibit distributed cavity effects, stimulated emission, and, above a threshold, mirrorless lasing at the band edges. The proposed work is to study, in conjunction with EC collaborators, the response of optically pumped helical cholesteric and other periodic liquid crystalline elastomers under mechanical strain. Participating graduate and undergraduate students will gain hands-on experience using the latest research techniques in laser physics and spectroscopy studying photonic band gap elastomers. In addition to gaining fundamental insights into the processes underlying the optical response of these materials, the proposed research will lead to mechanically tunable laser sources, switchable mirrors and tunable band-gap materials.Liquid crystal elastomers are novel rubber-like materials that dramatically change their optical properties when mechanically deformed. This unique property can be used to produce exceptional properties not possible with other materials; for example, they can be used to produce mechanically tunable wavelength selective mirrors, and large area, thin film lasers. The planned research will focus on exploring and utilizing these unique properties and effects. The high-risk materials research that led to the recent discovery of tunable 'rubber band' lasers would not have been possible without public funding of basic research. The proposed work, to be performed in collaboration with European Community scientists already engaged in the study of elastomeric materials, is needed to ensure U.S. presence at the forefront of this materials science and technology area. The project will educate participating graduate and undergraduate students in the cutting-edge interdisciplinary areas of soft materials characterization, laser physics and photonics, and is expected to impact on a variety of technologies ranging from telecommunications to artificial muscles.

液晶弹性体是一类新型软材料，其特点是取向顺序和应变之间的耦合，其机械变形会引起介电张量的变化。 胆甾型液晶弹性体由于其周期性结构，是光子带隙材料，其能带结构可以通过机械应变改变。光泵浦胆甾型液晶弹性体表现出分布式空腔效应、受激发射，并且在阈值以上，能带边缘出现无镜激光发射。拟议的工作是与 EC 合作者一起研究光泵浦螺旋胆甾型和其他周期性液晶弹性体在机械应变下的响应。参与的研究生和本科生将使用激光物理和光谱学研究光子带隙弹性体的最新研究技术获得实践经验。除了获得对这些材料光学响应过程的基本了解外，拟议的研究还将带来机械可调谐激光源、可切换镜子和可调谐带隙材料。液晶弹性体是新型橡胶类材料，可以极大地改变它们的性能。机械变形时的光学特性。这种独特的性能可用于产生其他材料无法实现的特殊性能；例如，它们可用于生产机械可调波长选择镜和大面积薄膜激光器。计划的研究将侧重于探索和利用这些独特的特性和效果。如果没有基础研究的公共资助，导致最近发现可调谐“橡皮带”激光器的高风险材料研究是不可能实现的。拟议的工作将与已经从事弹性体材料研究的欧洲共同体科学家合作进行，以确保美国处于该材料科学和技术领域的前沿。该项目将为参与的研究生和本科生提供软材料表征、激光物理和光子学等前沿跨学科领域的教育，预计将对从电信到人造肌肉等多种技术产生影响。