Circularly polarized light (CPL) is central to photonic technologies. A key challenge lies in developing a general route for generation of CPL with tailored chiroptical activity using low‐cost raw materials suitable for scale‐up. This study presents that cellulose films with photonic bandgaps (PBG) and left‐handed helical sense have an intrinsic ability for circular polarization leading to PBG‐based CPL with extraordinary |g | values, well‐defiend handedness, and tailorable wavelength by the PBG change. Using such cellulose films, incident light ranging from near‐UV to near‐IR can be transformed to passive L‐CPL and R‐CPL with viewing‐side‐dependent handedness and |g | values up to 0.87, and spontaneous emission transformed to R‐CPL emission with |g | values up to 0.68. Unprecedented evidence is presented with theoretical underpinning that the PBG effect can stimulate the R‐CPL emission. The potential of cellulose‐based CPL films for polarization‐based encryption is illustrated. The evaporation‐induced self‐assembly coupled with nanoscale mesogens of cellulose nanocrystals opens new venues for technological advances and enables a versatile strategy for rational design and scalable manufacturing of organic and inorganic CPL films for photonic applications.

中文翻译：

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发现用于光子学的手性光子纤维素膜的圆偏振电势

圆偏振光（CPL）是光子技术的核心。关键的挑战在于，使用适合规模化生产的低成本原材料，开发具有定制的按摩活性的CPL通用生产路线。这项研究表明，具有光子带隙（PBG）和左手螺旋感的纤维素膜具有固有的圆偏振能力，从而导致基于PBG的CPL具有非凡的|光学性能。克 | PBG的变化带来的价值，良好的手持性和可定制的波长。使用这种纤维素膜，可以将近紫外到近红外范围内的入射光转换为被动L-CPL和R-CPL，并具有视侧依赖的手感和||稳定性。克 | 值高达0.87，并且自发发射转换为R-CPL发射，其中| G | 值最高为0.68。前所未有的证据提供了理论基础，表明PBG效应可以刺激R-CPL的发射。说明了基于纤维素的CPL膜在基于偏振的加密中的潜力。蒸发诱导的自组装与纤维素纳米晶体的纳米级介晶相结合，为技术进步开辟了新场所，并为合理设计和可扩展地制造用于光子应用的有机和无机CPL薄膜提供了一种多功能策略。