Fiber optic devices including volume Bragg grating (VBG) elements are disclosed.
A fiber optic device may include one or more optical inputs, one or more VBG elements,
and one or more optical receivers. Methods for manufacturing VBG elements and for
controlling filter response are also disclosed. A VBG chip, and fiber optic devices
using such a chip, are also provided. A VBG chip includes a monolithic glass structure
onto which a plurality of VBGs have been recorded.