Squeezed-state-enhanced frequency-modulation spectroscopy

We analyze a simple model that demonstrates the feasibility of using optical squeezed states to enhance the detection sensitivity limits of frequency-modulation laser-absorption spectroscopy. The model shows that the most significant noise reduction would result by squeezing the weak frequency-modulated sidebands rather than the strong carrier and that losses in the optical detector could be made to set the limiting noise floor. By using currently available detectors, an order-of-magnitude improvement in the quantum-limited sensitivity of frequencymodulation spectroscopy may be possible.