Application of quantum inequalities to quantum optics

We establish a connection between quantum inequalities, known from quantum-field theory on curved spacetimes, and the degree of squeezing in quantum-optical experiments. We prove an inequality which binds the reduction of the electric-field fluctuations to their duration. The bigger the level of fluctuation suppression the shorter its duration. As an example of an application of this inequality is the case of squeezed light whose phase is controlled with $1\%$ accuracy for which we derive a limit of $-15\mathrm{dB}$ on the allowed degree of squeezing.