High-harmonic generation in solids

Abstract The last decade saw attosecond physics, traditionally focused on atomic and molecular gases, move rapidly into the condensed matter phase. This expansion was stimulated by experimental observation of high-harmonic generation (HHG) from solids. HHG, first observed in atomic gas a few decades ago, is a unique process underlying the creation of attosecond pulses and has many other applications involving imaging and controlling electron dynamics. Although insights from strong field atomic physics were instrumental to our understanding of HHG in solids, the unique properties of crystalline structure lead to a rich variety of new phenomena unique to solids. This has resulted in a rapid expansion of the field, as is evidenced by the growing body of research at the intersection of attosecond physics and condensed matter. Here, we review some notable advances over the past decade, highlighting open questions and some recent developments.