Sub-cycle dynamics in the attosecond transient absorption spectroscopy of solid

<p indent="0mm">As a cutting-edge spectral analysis method, attosecond transient absorption spectroscopy is gradually transitioning from simple atomic and molecular systems to complex condensed matter systems. According to the Keldysh parameter, this article classifies several representative works that use this technology to study ultrafast electron dynamics in solids, aiming to provide researchers with an overview of the technology and a reference for future development directions.