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Abstract Glasses are generally assumed to be isotropic and there are no literature reports of elastic anisotropy for molecular glasses. However, as glasses formed by physical vapor deposition can be structurally anisotropic, it is of interest to investigate the elastic anisotropy in these materials. Micro‐Brillouin light spectroscopy is used in several experimental geometries to determine the elastic stiffness tensors of three glass films of itraconazole vapor‐deposited at substrate temperatures (T_sub) of 330, 315, and 290 K, respectively. Significant elastic anisotropy is observed and, in these glasses, the elastic anisotropy shows a strong correlation with the molecular orientation. The out‐of‐plane and in‐plane Young's moduli of the highT_sub(330 K) sample, which features a predominantly vertical molecular orientation, exhibit a high anisotropy ratio of 2.2. The observed elastic anisotropy is much larger than those previously observed in liquid crystals and even many crystalline solids. 

Abstract Photothermal energy conversion is of fundamental importance to applications ranging from drug delivery to microfluidics and from ablation to fabrication. It typically originates from absorptive processes in materials that—when coupled with non‐radiative dissipative processes—allow the conversion of radiative energy into heat. Microstructure design provides versatile strategies for controlling light–matter interactions. In particular, the deliberate engineering of the band structure in photonic materials is known to be an effective approach to amplify absorption in materials. However, photonic amplification is generally tied to high optical contrast materials which limit the applicability of the concept to metamaterials such as microfabricated metal–air hybrids. This contribution describes the first observation of pronounced amplification of absorption in low contrast opals formed by the self‐assembly of polymer‐tethered particles. The dependence of the amplification factor on the length scale and degree of order of materials as well as the angle of incidence reveal that it is related to the slow photon effect. A remarkable amplification factor of 16 is shown to facilitate the rapid “melting” of opal films even in the absence of “visible” absorption. The results point to novel opportunities for tailoring light–matter interactions in hybrid materials that can benefit the manipulation and fabrication of functional materials.