Based on previous reports on the optical microscopy contrast of mechanically exfoliated few layer CrCl transferred on 285 nm and 270 nm SiO on Si(100), we focus on the experimental determination of an effective mean complex refractive index via a fitting analysis based on the Fresnel equations formalism. Accordingly, the layer and wavelength-dependent absorbance and reflectance are calculated. Layer and wavelength-dependent optical contrast curves are then evaluated demonstrating that the contrast is significantly high only around well-defined wavelength bands. This is validated a posteriori, by experimental UV-Vis absorbance data. The present study aims to show the way towards the most reliable determination of thickness of the 2D material flakes during exfoliation.
Zinc ferrite (ZnFeO, ZFO) has gained attention as a candidate material for photoelectrochemical water oxidation. However, champion devices have achieved photocurrents far below that predicted by its bandgap energy. Herein, strong optical interference is employed in compact ultrathin film (8-14 nm) Ti-doped ZFO films deposited on specular back reflectors to boost photoanode performance through enhanced light trapping, resulting in a roughly fourfold improvement in absorption as compared to films deposited on transparent substrates.
Herein, we report the high-temperature solid-state synthesis and intriguing optical features of Bi3+/Ln3+ doped Ca2YTi2Ga3O12 (CYT). The optical properties of CYT were fine-tuned by judiciously substituting Zr4+ ions at Ti4+ sites and Bi3+, Ln3+ ions at Y3+ sites. All these compounds are crystallized in a cubic crystal system with an Ia-3d (no.
State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures, MOE Key Laboratory of New Processing Technology for Nonferrous Metals and Materials, and School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China.
Zero-dimensional metal halides with diverse structures and rich photophysical properties have been reported. However, achieving multimode dynamic luminescence and efficient near-infrared (NIR) emission under blue light excitation in a single system is a great challenge. Herein, Sb-doped hybrid Cd(II) halides were synthesized by a large scale synthesis process at room temperature.
Generating wavelength-tunable picosecond laser pulses from an ultrafast laser source is essential for femtosecond stimulated Raman scattering (FSRS) measurements. Etalon filters produce narrowband (picosecond) pulses with an asymmetric temporal profile that is ideal for stimulated resonance Raman excitation. However, direct spectral filtering of femtosecond laser pulses is typically limited to the laser's fundamental and harmonic frequencies due to very low transmission of broad bandwidth pulses through an etalon.
Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China. Electronic address:
Raman-based methods are promising for in vivo biological detection but face challenges due to fluorescence interference in measurement accuracy.
This study introduces a dual-wavelength Raman method using two different lasers to improve Raman signal quality by eliminating fluorescence effects.
The method was successfully applied to early cancer diagnosis, identifying significant biomolecules in esophageal tissue that indicate different malignancy levels.
