A method for fabricating a liquid crystal display device includes providing an LCD panel that includes a photopolymerizable compound in its liquid crystal layer; and forming alignment sustaining layers by polymerizing the photopolymerizable compound in the liquid crystal layer of the LCD panel with the liquid crystal layer irradiated with light and supplied with a voltage simultaneously. To extend the range of frequency shifting beyond the width of a single band gap, the intrinsic control parameters are spatially varied across the PC to form a band gap gradient. For example, the average composition of nitrogen can be designed to be between 0.