Nonadiabatic Effects of Atomic Coherence on Laser Intensity Fluctuations in Electromagnetically Induced Transparency

In an electromagnetically induced transparency system, the atoms have long-lived coherence compared to the cavity lifetime and interact nonadiabatically with the laser fields. We show that the high frequency fluctuations of both the intensities and the intensity difference can be squeezed below the shot noise limit due to the nonadiabatic effects. This noise squeezing can be used to enhance the precision in the short time measurements based on the intensities or the intensity difference.