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Chiral semiconductor nanostructures have received enormous attention due to their emerging circularly polarized luminescence (CPL) properties. However, compared with well‐studied photoluminescence (PL), the reported CPL is much weaker and more challenging to be modulated. Herein, we describe a new approach for acquiring the intense and tunable CPL from inorganic chiral photonic crystals (CPCs) doped with semiconductor quantum dots (QDs). Unprecedentedly, the sign, position and intensity of CPL peaks can be precisely controlled by manipulating either the photonic band gap of CPCs or luminescence wavelength of QDs and a giant absolute dissymmetry factor |glum| up to 0.25 is obtained. More importantly, the origin of the CPL modulation is clearly elucidated by both experiment and theory. This work lays the foundation for the construction of next‐generation high‐performance CPL‐based devices. [ABSTRACT FROM AUTHOR]

Inorganic single crystals with anisotropic structures usually suffer from high brittleness and stiffness. Flexible polymers are used to replace inorganic crystals, but the hot‐stretching‐induced orientation process is tedious, and oriented molecular chains tend to revert to random coils during aging. To overcome these obstacles and using the similarities between sub‐1 nm nanowires (NWs) and linear polymers, we successfully fabricated anisotropic, transparent, flexible, and stable (ATFS) NW films with great potential for optical applications through a wet‐spinning method. The NW films show birefringence, and their birefractive index is higher than that of many polymers. They also showed polarized absorption of UV light and anisotropic scattering of visible light. The integrated films composed of NWs and quantum dots showed good fluorescence polarization. The tedious synthesis of quantum rods and fabrication of oriented polymer films can thus be avoided. [ABSTRACT FROM AUTHOR]

An ultrastrong and broadband chiroptical response is key but remains challenging for many device applications. A simple and cost-effective bottom-up method is introduced to fabricate large-area long-range ordered chiral ultrathin films with the Langmuir-Schaeffer technique using gold nanowires as building blocks. Significantly, as-prepared ultrathin films display giant optical activity across a broad wavelength range covering visible and near infrared regions with an anisotropic factor of up to 0.285, which is the record value for bottom-up techniques. Detailed experimental result and theoretical analysis disclose that such remarkable optical activity originates from birefringence and dichroism of the well-aligned Au nanowire layers in the ultrathin films. The universality of this facile strategy for constructing chiral ultrathin films is further demonstrated with many other one-dimensional nanomaterials. [ABSTRACT FROM AUTHOR]

Chiral semiconductor nanostructures have received enormous attention due to their emerging circularly polarized luminescence (CPL) properties. However, compared with well‐studied photoluminescence (PL), the reported CPL is much weaker and more challenging to be modulated. Herein, we describe a new approach for acquiring the intense and tunable CPL from inorganic chiral photonic crystals (CPCs) doped with semiconductor quantum dots (QDs). Unprecedentedly, the sign, position and intensity of CPL peaks can be precisely controlled by manipulating either the photonic band gap of CPCs or luminescence wavelength of QDs and a giant absolute dissymmetry factor |glum| up to 0.25 is obtained. More importantly, the origin of the CPL modulation is clearly elucidated by both experiment and theory. This work lays the foundation for the construction of next‐generation high‐performance CPL‐based devices. [ABSTRACT FROM AUTHOR]