Advanced Optical Materials最新文献

Nanometric Ge Films for Ultrafast THz Modulation

Nanometric germanium films, vastly thinner than terahertz wavelengths, have been integrated with a responsive metasurface of metallic terahertz asymmetric split ring resonators on a low-loss flexible substrate (cyclic olefin copolymer film). These ultrathin, flexible, and ultrafast functional metasurfaces enable efficient, low-power terahertz modulation. For further information, see article number 2402010 by Jianqiang Gu, Ranjan Singh, and co-workers.

Optimized Er-Doped LiNbO₃ Quantum Memory Platform

In the study by Andrej Kuznetsov, Kiwon Moon, and co-workers (see article number 2401374), an optimized approach for fabricating an efficient solid-state photonic quantum memory platform is proposed. This approach relies on dynamic defect annealing occurring in the LiNbO₃ matrix material during its implantation with Er ions at elevated temperatures. The resulting platform, with minimized crystalline disorder and enhanced optical activity, is promising for realizing robust quantum memory with extended storage times and high efficiencies.

Highly Refractive Transparent Half-Heuslers for Near-Infrared Optics

Advanced control of light focusing, reflection, and transmission is possible by using highly refractive transparent materials. In article number 2402295, Akihiro Ishii, Hitoshi Takamura, and co-workers report the discovery of 22 ternary half-Heuslers that exhibit higher refractive indices with wider band gaps than conventional high-refractive-index transparent materials in the near-infrared region. Material design strategies for achieving a high index and wide gap are also explained.

Retina-Like Neuromorphic Visual Sensor for Sensing UV Light

A novel retina-like InGaO thin-film-based neuromorphic visual sensor is presented in article number 2402193 by Weihua Tang, Zeng Liu, and co-workers. The device enables sensing of broad-spectrum ultraviolet light, has excellent photoelectric synaptic performances, and can effectively mimic a variety of image sensing and pre-processing functions of the human retina. It provides a new method for human to perceive invisible ultraviolet light.

Exploring the Resonances of Symmetry-Protected Modes for Multitasking

Fadi Baida and co-workers have designed a sub-wavelength meta-device to excite multiple continuum-integrated states (BICs) under varying illumination conditions and wavelengths (see article number 2401558). These resonances enable a range of applications, including acousto-optic modulation by coupling with surface acoustic waves, second harmonic generation (SHG) exploiting the nonlinear properties of lithium niobate, electro-optic modulation and pyroelectric applications, both enhanced by strong electric field confinement associated with the electro-optic and pyroelectric properties of lithium niobate.

Response of Indirect Excitons to Non-Uniform Elastic Strain in MoS₂ Flakes

In article number 2401728, Lifu Zhang, Zhenpeng Hu, Yuan Yan, Xuewen Fu, and co-workers report the abnormal response of indirect excitons to non-uniform elastic strain in MoS₂ flakes, fundamentally distinct from the linear energy-shift behavior of direct excitons. Such abnormal phenomenon arises from the strain-induced competition between two indirect bandgap transitions and the spatial exciton funnel effect in the non-uniform strain field.

Effect of Defects and Strain on Photoluminescence in Metal Thiophosphates

This cover image displays the surface topography of 2D AgScP₂S₆, where sulfur vacancies act as color centers (depicted by the bottom right figure). Structural ‘crater-like’ defects on the surface enhance and modulate light emission originating from these vacancies, resulting in broadband visible light. For further details, see article number 2400481 by Abhishek Mukherjee, Svetlana V. Boriskina, and co-workers.

Surface-enhanced Raman spectroscopy (SERS) detection is a crucial technology for rapid sensing and “fingerprinting”, achieved through the combination of Raman spectroscopy and arrays of noble metal nanoparticles (NPs). This study introduces a low-cost biomimetic-inspired approach to fabricate rose petal structured micro/nano hierarchical structures with silver (Ag) film, serving as a reliable SERS substrate. These substrates are thoroughly compared by replicating the upper surface of rose petals of different colors into a transparent polydimethylsiloxane (PDMS) mixture and subsequently sputtering Ag film of varying thicknesses. Ultimately, the white negative rose PDMS replica is chosen, demonstrating a high enhancement factor, good batch-to-batch reproducibility, high stability, and high sensitivity for crystal violet (CV), an organic contaminant with mutagenic and toxigenic properties. In a proof-of-concept experiment, the multiplex detection capability of this SERS substrate is demonstrated by analyzing a combination of two sets of analytes (CV and methylene blue as well as CV and Nile blue A). Furthermore, this SERS substrate is utilized to test tau protein and amyloid β peptides, both recognized biomarkers of Alzheimer's disease. This study illustrates that the proposed 3D SERS substrate exhibits significant potential for the highly sensitive and rapid detection of biomolecules in practical applications.