Density-gradient-controlled high-order harmonic generation from a plasma on a solid surface irradiated by midinfrared laser pulsesRemoveMikhail V. Rozhko, Nikita V. Yakushkin, Egor F. Astashkin, Yaroslav O. Romanovskii, Aleksandr V. Mitrofanov, Aleksandr A. Voronin, and Dmitry A. Sidorov-BiryukovPhys. Rev. A 113, 043515 (2026)
