METHOD OF SELECTIVELY CHEMICALLY CHANGING INSIDE OF INORGANIC MATERIAL AND INORGANIC MATERIAL INSIDE OF WHICH IS SELECTIVELY CHEMICALLY CHANGED

摘要

An inorganic material (3) containing rare-earth ions and/or transition metal ions is irradiated with a pulse laser beam (1) whose focal point (2) is inside the inorganic material (3). The inorganic material is a glass or crystal consisting of one or more of oxides, halides, and chalcogenides. The rare-earth ions include ions such as of Ce, Nd, Pr, Sm, Eu, Tb, Dy, Tm, and Tb. The transition metal ions include ions such as of Ti, Mn, Cr, V, Fe, Cu, Mo, and Ru. When the focal point (2) of the pulse laser beam (1) is moved relative to the inorganic material (3), a region of predetermined pattern where the ionic valences have changed is formed inside the inorganic material (3). The pulse laser beam preferably has a pulse width of below 1 picosend. Though the valences of the rare-earth or transition metal ions change at and around the focal point (2), they do not change in the other regions. Therefore a chemically changed region of necessary pattern is formed inside the inorganic material (3). Such a processed inorganic material has a specific region thereinside where optical characteristics are selectively changed, and hence is used as, e.g., a memory material featured by the changed optical characteristics and a functional material for light-emitting devices.