High pressure fibre optics

21.06.2013, 00:00

Newsletter 6

The effective Kerr nonlinearity of hollow-core kagomé-style photonic crystal fiber (PCF) filled with argon gas increases to ~15% of that of bulk silica glass when the pressure is increased from 1 to 150 bar, while the zero dispersion wavelength shifts from 300 to 900 nm. The group velocity dispersion of the system is uniquely pressure-tunable over a wide range while avoiding Raman scattering—absent in noble gases—and having an extremely high optical damage threshold. As a result, detailed and well-controlled studies of nonlinear effects can be performed, in both normal and anomalous dispersion regimes, using only a fixed-frequency pump laser. The system has great potential for the realization of reconfigurable supercontinuum sources, wavelength convertors and short-pulse laser systems. Other noble gases may be used: for instance, Xe would attain a nonlinearity comparable to that of silica at a pressure of 150 bar. Gas-filled kagomé PCF thus may be viewed as transforming gases into "honorary solid state materials", with the additional advantages of tunable dispersion and extremely high optical damage resistance.

Contact: mohiudeen.azhar(at)mpl.mpg(dot)de
Group: Russell Division
Reference: M. Azhar et al., Opt. Express 21, 4405-4410 (2013).