Fabrication of a periodically poled laminar domain structure with a pitch of a few micrometers by applying an external electric field

The fabrication of a fine-pitch laminar domain structure in a lithium niobate (LiNbO3) single crystal is reported. Special emphasis is placed on how to fabricate the structure homogeneously, in which it was found that the application of multiple pulses is beneficial, and how to fabricate the structure in a relatively thick substrate, in which it was found that the application of a accumulated static field on the multiple pulses is useful. The following questions are discussed: Why the inverted domain structure corresponds to the structure of the electrode on the +z face, and why the application of multiple pulses is useful in the fabrication of a homogeneous laminar domain structure.