| 摘要 |
<p>A periodic interference pattern of coherent waves is created in in two or three dimensions, D, by generating at least D+1 waves, each wave having substantially the same wavelength, ? , and traveling substantially in a unique direction, k<SUB>n</SUB>, and directing the waves such that at least a portion of each wave intersects in a common excitation region to create the interference pattern. The directions of the waves, k<SUB>n</SUB>, are selected such that the interference pattern within the excitation region forms a Bravais lattice having a symmetry, a shape to the primitive cell defined by the D-dimensional region closest to any chosen lattice point, and a periodicity relative to the wavelength,? , that is larger than the smallest periodicity Bravais lattice having the same symmetry and identically defined primitive cell shape that can be created at the wavelength, ?. The directions of the waves, k<SUB>n</SUB>, do not all lie on a D-dimensional set of mutually orthogonal axes.</p> |
