In case you did not see this news item, I just thought I had to share it since it is so appropriate for the holidays (Source: Carnegie Institution for Science):
If you are still deciding on what to give the woman (or microwave engineer) who has everything this holiday season, then researchers in Washington may have solved that last minute gift problem – microwaved diamonds. Members of Carnegie Institution’s Geophysical Laboratory have used a chemical vapor deposition (CVD) method to grow synthetic diamonds for their experiments. Unlike other methods, which mimic the high pressures deep within the earth where natural diamonds are formed, the CVD method produces single-crystal diamonds at low pressure. The resulting diamonds, which can be grown very rapidly, have precisely controlled compositions and comparatively few defects.
The Carnegie team then annealed the diamonds at temperatures up to 2,000° C using a microwave plasma at pressures below atmospheric pressure. The crystals, which are originally yellow-brown if produced at very high growth rates, turned on the size of crystals or the number of crystals, because the method is not limited by the chamber size of a high pressure press. The microwave unit is also significantly less expensive than a large high-pressure apparatus.
Unfortunately, those late holiday shoppers will still have to go to the store rather than the lab for that diamond ring because the high-quality, single crystal diamond made possible by the new process has a wide variety of applications in science and technology rather than for jewelry. These include the use of diamond crystals as anvils in high-pressure research and in optical applications that take advantage of diamond’s exceptional transparency. Among the more exotic future applications of the pink diamonds made in this way is quantum computing, which could use the diamonds’ NV centers for storing quantum information.