Luminescent diamond and method of making the same

Abstract

Luminescent diamond is made subjecting a volume of diamond grains and catalyst material to high-pressure/high-temperature (HPHT) conditions. A pressure apparatus and/or a pressure cell is specially configured to impose a differential or asymmetric pressure onto the diamond volume during the HPHT conditions. This subjects the diamond grains to differential strain that increases the degree of plastic deformation of the diamond grains to increase the formation of nitrogen vacancy centers. Diamond pellets formed by such process and subjected to differential pressure can have an aspect ratio, or an aspect ratio change, of greater than one. The temperature of the HPHT process is 1.800° C. or less to facilitate desired nitrogen migration to preferentially promote formation of NV centers over NVN and N3 centers in the diamond pellets to provide a degree of luminescence in a red wavelength spectrum greater than diamond pellets formed by some other HPHT processes.

Dependencies are inferred from the claim text.