The determinations of water status incorporated in hydrous minerals are of considerable significances in geoscience fields. Coincidentally, the aqueous sensitivity of terahertz radiation has motivated numerous explorations in several cross-domain applications. Terahertz time-domain spectroscopy is employed as a major probing technique coupling of traditional detecting methods to uncover the mask of water status in copper sulfate pentahydrate as well as mineral quartz in this article. Based on the quantitative identification of water status in copper sulfate pentahydrate, the water incorporated in mineral quartz is verified qualitatively. Notable differences of optical constants originating from the water content are obtained for copper sulfate pentahydrate and mineral quartz. These present works indicate that terahertz technology can be considered as a promising method to satisfy the ever-increasing requirements in hydrous mineral analyses.

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Nowadays, the mineral resources formed by geological processes have been effectively utilized with the boom exploration of novel technologies. Traditional analytical methods, such as X-ray Fluorescence, X-ray diffraction, and Scanning electron microscopy, remain the commonly used approaches for resource detection. However, recent accelerations in terahertz component progress have promoted researchers to discover more potential technologies in mineral resource exploration. In this article, the various porosities and calcination products of Chlorite mica carbonate schist, a mineral resource and potent medicine, are detected using the terahertz time–domain spectroscopy. The terahertz constant measurement of Chlorite mica carbonate schist tablets including the amplitude and phase values was carried out. After Fourier transforms, notable differences of absorption coefficients and refractive index are observed from these experimental samples, which have compelling indications to quantitatively analyze the pore conditions and pyrolytic properties of mineral resources. This active research has vital implications for the rock reservoir properties analysis and mineral energy utilization. It is also identified that terahertz time–domain spectroscopy can be considered as a promising method for the qualitative, reliable, and efficient detection of mineral resources.

Extremely strong‐field terahertz (THz) radiation in free space has compelling applications in nonequilibrium condensed matter state regulation, all‐optical THz electron acceleration and manipulation, THz biological effects, etc. However, these practical applications are constrained by the absence of high‐intensity, high‐efficiency, high‐beam‐quality, and stable solid‐state THz light sources. Here, the generation of single‐cycle 13.9‐mJ extreme THz pulses from cryogenically cooled lithium niobate crystals and a 1.2% energy conversion efficiency from 800 nm to THz are demonstrated experimentally using the tilted pulse‐front technique driven by a home‐built 30‐fs, 1.2‐Joule Ti:sapphire laser amplifier. The focused peak electric field strength is estimated to be 7.5 MV cm−1. A record of 1.1‐mJ THz single‐pulse energy at a 450 mJ pump at room temperature is produced and observed that the self‐phase modulation of the optical pump can induce THz saturation behavior from the crystals in the substantially nonlinear pump regime. This study lays the foundation for the generation of sub‐Joule THz radiation from lithium niobate crystals and will inspire more innovations in extreme THz science and applications.

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