The GaxIn1-xAsyP1-y layers grown by LP-MOVPE at reduced growth temperatures exhibit a high degree of ordering. This effect is used to fabricate polarisation-dependent devices in the optical fibre wavelength regime. A non-gaseous source configuration (ngs) based on the group-V precursors TBAs and TPB enables the growth of up to 700 nm thick lattice matched quaternary absorption layers. The highest degree of ordering, is observed at a growth temperature of T-g = 575degreesC with nearly the same phosphorous to arsenic content in the solid phase. This indicates a strong additional contribution of a roup-V ordering, the ordered In1-xGaxAsyP1-y absorption layer results in high quantum efficiency of up to 0.2 A/W with up to 50% anisotropy for polarised light. A first polarisation switch is fabricated combining a pin-diode and a FET exhibiting 55 dB polarisation contrast. These results indicate the high potential of this approach for on-line polarisation mode dispersion (PMD) compensation circuits.