Reduction of Guided Acoustic Wave Brillouin Scattering in Photonic Crystal Fibers

Thermally excited transverse phonons in glass fibers generate guided acoustic wave Brillouin scattering (GAWBS) which afflicts the propagating light with phase and polarization noise. This excess noise is a major limitation for fiber-based squeezing sources as well as for the transmission of quantum information through fibers. In order to achieve quantum states of high quality it is therefore important to reduce the harmful effect of GAWBS. The thermal nature of GAWBS naturally allows for a reduction by cooling the fiber. Alternatively, subtracting the correlated noise of two closely spaced pulses leads to a cancellation. These methods, however, are inconvenient for fiber-based squeezing sources and inapplicable in practical quantum information transmission systems.