Can you combine wavelengths to ionize atoms

If I have an atom with energy levels of -4 ev, -2 ev -1 ev and 0 ev and I radiate it with photons which cover a continuous range from 0 to 2 ev is it not possible for a 2 ev photon to move the electron from -4 to -2 and then a 1 ev photon to move it from -2 to -1 and then a 2 ev photon to free the electron with a kinetic energy of 1 ev? Most material talks about a minimum frequency to eject an electron but I think that only applies it the source is a single frequency. Am I correct? Thanks!