Moving High-Field Domains

Summary

High-field domains that remain attached to one electrode are stationary. Under a large variety of circumstances they separate from the electrode and move through the crystal. Such moving high-field domains can have significant technical importance, e.g., as the Gunn domain. Others can be helpful to identify parameter relations of a specific device, and still others may be used for demonstration or simply as estetical display. Unfortunately, some of these domain instabilities also produce disturbing electronic, mostly low frequency noise. In general, a solid understanding of the conditions that lead to such moving or unstable domains is essential for many devices that operate at high electric fields.