Measurement of dephasing time using incoherent light in the Kerr shutter configuration

We propose a convenient signal-selective method to measure the dephasing time using incoherent light performed in the Kerr shutter configuration. The advantage of this method is easy alignment, which allows one to obtain a better signal-to-noise ratio than with ordinary forward two-beam degenerate four-wave mixing. The dephasing time of Cresyl Violet doped in a polymethyl methacrylate film obtained by this method is compared with the result from ordinary two-beam degenerate four-wave mixing.