Long since a condensed matter theorist, I have had two years' experience
as an experimentalist in the field of hot-filament chemical vapor
deposition (HFCVD) of thin diamond films on various substrates (mainly
silicon) when I was a graduate student in China. I have made
important breakthroughs on two major issues that the CVD diamond
community had been trying hard to solve: (i) low nucleation density
and (ii) unable to achieve heteroepitaxial growth. I have been
the first who has achieved, using HFCVD, epitaxially oriented growth
of diamond films on silicon wafers, and shown that a 
-SiC
buffer layer is not a necessary condition for epitaxy of diamond on
Si, contrary to what many people had believed. I have invented two
methods (electron-emission enhanced nucleation and very low pressure
nucleation) which achieve nucleation densities two to three orders of
magnitude higher than usual. My work has stimulated many subsequent
studies.