Muonic Atom As An Acceptor Centre In Diamond

Polarized negative muons were used to study the behaviour of the boron acceptor centre in diamond produced by the chemical vapour deposition (CVD) method. The temperature dependence of the muon spin relaxation rate and spin precession frequency were measured in the range of 20 330 K in a transverse magnetic field of 14 k0e. The muon polarization amplitude P(t = 0) does not depend on the temperature and the muon spin relaxation rate decreases as the temperature increases. For the first time a negative shift of the muon spin precession was observed in diamond. The measurements show that the magnetic susceptibility of the CVD sample is negligible (chi = 4.13(2) . 10(-7) cm(3)/g at 20 K) and it could not be the reason of the negative shift muon spin precession frequency. The negative shift of the muon spin precession frequency is tentatively attributed to an anisotropic hyperfine interaction in the boron acceptor in diamond.