Behaviour of a muonic atom as an acceptor centre in diamond

TL;DR

This study uses polarized negative muons to investigate the behaviour of boron acceptor centres in synthetic diamond, revealing a negative muon spin precession shift and temperature-dependent relaxation, providing insights into impurity interactions.

Contribution

It introduces the use of muonic atoms to probe boron acceptors in diamond and reports the first observation of a negative muon spin precession shift in this material.

Findings

Negative shift of muon spin precession observed in diamond

Temperature dependence of muon spin relaxation measured

Magnetic susceptibility similar to natural diamond

Abstract

Polarized negative muons were used to study the behaviour of the boron acceptor centre in synthetic diamond produced by the chemical vapour deposition (CVD) method. The negative muon substitutes one of the electrons in a carbon atom, and this muonic atom imitates the boron acceptor impurity in diamond. 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 kOe. For the first time a negative shift of the muon spin precession was observed in diamond. It is tentatively attributed to an anisotropic hyperfine interaction in the boron acceptor. The magnetic measurements showed that the magnetic susceptibility of the CVD sample was close to that of the purest natural diamond.