Using multiply diffracted P waves and first-principles computations of the thermoelastic properties of liquid iron-rich alloys, we show that the core of Mars is smaller and denser than previously thou...

The long-term retention of substantial atmospheres in close-in exoplanets presents a major challenge to classical hydrodynamic escape theory, which predicts rapid mass loss under intense stellar irrad...

Newswise — Gas sensing technology is a cornerstone of industrial safety, environmental monitoring, and public health, enabling early detection of hazardous gas leaks and precise tracking of pollutant emissions. With the rapid development of industrial automation and increasingly stringent environmental regulations, there is a growing demand for compact, low-cost multi-gas detection systems that can perform real-time simultaneous measurements. Light-induced thermoelastic spectroscopy (LITES) has emerged as a promising trace gas detection technique due to its high sensitivity, excellent selectivity, and non-contact measurement capability. Unlike conventional quartz-enhanced photoacoustic spectroscopy, LITES detects the periodic photothermal signal generated by gas molecules absorbing modulated laser light, making it suitable for harsh environments such as corrosive atmospheres and high-temperature flames. However, existing multi-gas LITES systems rely on either time-division multiplexing, which cannot achieve true simultaneous detection, or conventional frequency-division multiplexing, which requires independent demodulation units for each channel, leading to increased system complexity, cost, and inter-channel crosstalk. In a new paper published in Light: Advanced Manufacturing, a team led by Professor Yufei Ma from the National Key Laboratory of Laser Spatial Information at Harbin Institute of Technology, China, has developed a novel mixed-frequency heterodyne demodulation (MHD) architecture that addresses these limitations. Using this architecture, the team...

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