Red-shift law of intense laser-induced electro-absorption in solids

A theoretical study on the red-shift of laser-induced electro-absorption is presented.It is found that laser-induced red-shift scales with the cube root of the pump laser intensity in the optical tunneling regime and has an obvious deviation from this scale in the multi-photon regime.Our results show that in the optical tunneling regime,the laser-induced red shift has the same law as that in the direct current(DC)approximation.Though the scales are the same in the optical tunneling regime,the physical pictures in the two cases are quite different.The electro-absorption in the DC case is a tunneling-assisted transition process,while the laser-induced electro-absorption is a mixed multi-photon process.