The interaction of light waves with electrons in solids allows controlling the electron motions on attosecond timescales. In our paper https://doi.org/10.1103/PhysRevLett.134.176903 published in Physical Review Letters, we demonstrate that optical waves shaped by superposition of the fundamental and third harmonic frequencies can be used to separate quantum electron tunneling from other processes contributing to the generation of high harmonic frequencies. The paper was selected by the editor as an Editor's Suggestion.