Attenuation Coefficient

The basic notes, rests and harmonies of Western music arose as humans heard how sounds traveled through the first large temples, built more than 2,000 years ago

Two-photon polymerization is a potential method for nanofabrication to integrate nanomaterials based on femtosecond laser-based methods. Challenges in the field of 3D nanoprinting include slow layer-by-layer printing and limited material options as a result of laser-matter interactions.

Passive mode-locked technology utilizes saturable absorbers' nonlinear absorption effect to regulate the cavity's loss and phase to generate mode-locked pulses. Graphene has a unique energy bandgap structure, a low absorption coefficient, a considerable modulation depth, and an ultrawide operating spectral range (300–2,500 nm).

High-temperature shock (HTS) is an emerging synthesis method with kinetics-dominated non-equilibrium characteristics, which can achieve an ultrafast heating/cooling rate of ~105 K/s and a peak temperature larger than ~3000 K within a time scale of seconds or milliseconds, and is widely used in the preparation of high entropy content, thermodynamic metastable phase and defect-rich materials.

Applications based on Wi-Fi CSI (Channel state information), such as indoor positioning, human detection - GitHub - espressif/esp-csi: Applications based on Wi-Fi CSI (Channel state information), s...

All-inorganic, lead-free perovskite-derivative metal halides are promising in optoelectronics. However, it remains challenging to realize efficient near-infrared (NIR) luminescence in these materials.

Photonic systems are quickly gaining traction in many emerging applications, including optical communications, lidar sensing, and medical imaging. However, the widespread adoption of photonics in future engineering solutions hinges on the cost of manufacturing photodetectors, which, in turn, largely depends on the kind of semiconductor utilized for the purpose.

Metasurfaces are highly versatile for manipulating the amplitude, phase, or polarization of light. During the last decade, metasurfaces have been proposed for a vast range of applications—from imaging and holography to the generation of complex light field patterns. Yet, most optical metasurfaces developed to date are isolated optical elements that work only with external light sources.

Acoustic beam shaping with high degrees of freedom is critical for ultrasound imaging, acoustic regulation, and stimulation. The ability to fully regulate the acoustic pressure profile relative to its propagation path remains to be achieved.

A new publication in Opto-Electronic Science reports how high-quality diamonds empower narrowband deep ultraviolet photodetection.

Researchers led by Prof. Zhang Weijun from the Hefei Institutes of Physical Science (HFIPS) of the Chinese Academy of Sciences (CAS) have found that a decrease of about 35% of single scattering albedo (SSA) at 365–405 nm would cause a 46% decrease in direct radiative forcing (DRF) efficiency at ground albedo. The research was published in Science of the Total Environment.

Analog Lorenz Attractor Computer1. The Origin of Analog ComputerOne of the main purposes of analog circuits is to solve mathematical problems, such as building a circuit corresponding to a nonlinear differential equation and analyzing the phase plane characteristics of it by observing its output voltage with an oscilloscope or analog plotter. I will take a famous nonlinear differential equation, the Lorenz…

Microplastics are tiny plastic particles less than 5 mm in diameter that have emerged as a novel marine environment pollutant. Microplastics usually result from a breakdown of larger plastic debris but can also be generated from plastic microbeads used in personal care products.

We've previously manufactured some cool composite materials and they were a big success: we prepared materials suitable for mechanical use, such as the Prusament PC Blend Carbon Fiber and Prusament PA11 Carbon Fiber. To make the next step, we decided to...

The greatest hazard for humans on deep-space exploration missions is radiation. To protect astronauts venturing out beyond Earth's protective magnetosphere, advanced passive radiation protection is highly sought after. In search of innovative radiation-shields, biotechnology appeals with suitability for in-situ resource utilization (ISRU), self-regeneration, and adaptability. Certain fungi thrive in high-radiation…

Black carbon (BC) is the result of incomplete combustion of fossil fuels and biomass, with strong light absorption. It is second only to carbon dioxide as a climate-forcing factor for atmospheric warming. Deposition of BC on snow and ice surfaces reduces albedo, accelerates glacier and snow cover melting, and alters hydrological processes and water resources in the region.

Quantitative photoacoustic tomography (QPAT) is a medical imaging technique that combines laser-induced photoacoustic signals and ultrasound detection to create detailed three-dimensional images of biological tissues. The process involves irradiating biological tissues with short laser pulses. These pulses are absorbed by light-absorbing molecules (chromophores) within the tissues, leading to rapid heating and the…

Ultrafast extreme ultraviolet (XUV) spectroscopy is a powerful technique for probing the dynamics of atoms and molecules with attosecond time resolution. However, conventional XUV absorption measurements only provide information about the imaginary part of the complex refractive index, which is related to the absorption coefficient. The real part of the refractive index, which describes the chromatic dispersion of…

Particles in the atmosphere affect global climate. For example, the black carbon from burning fossil fuels absorbs and radiates light and heat. To calculate the effects of aerosols on climate, scientists rely on simulated aerosol fields. How these models represent aerosol mixing state potentially introduces large uncertainties into climate calculations. This is because the simulated aerosol optical properties—how…

A team from the Hefei Institutes of Physical Science of the Chinese Academy of Sciences has developed a high-sensitivity differential Helmholtz photoacoustic cell and successfully applied it to methane detection.