Shallow acceptor centres in silicon studied by means of spin rotation of negative muons

Abstract

The residual polarization of negative muons has been studied for phosphorus-doped ([P]: 1.6 × 10 13 cm −3 ) and antimony-doped ([Sb]: 2 × 10 18 cm −3 ) silicon crystals. The measurements were carried out in a transverse magnetic field of 0.1 T over the temperature region 4 K-300 K. The ionized and neutral states of the µ Al pseudo-acceptor were observed in antimony-doped silicon for the first time. The rate of transition from the neutral to the ionized state of the acceptor was found to be equal to 1.2 × 10 6 s −1 over the temperature range 4 K-12 K. The estimated rates of relaxation of the magnetic moment of the acceptor-centre electron shell are 5 × 10 10 s −1 and 1.6×10 12 s −1 in phosphorus-doped silicon and 6×10 11 s −1 and 6.7×10 12 s −1 in antimony-doped silicon at 4 K and 15 K respectively. The experimental results obtained are interpreted in terms of spin-lattice relaxation of the acceptor magnetic moment and of the acceptor-donor pair formation.

Extending WiMDA for the data analysis of µ −SR experiments

“…At longer times, where the long-lived decay background dominates, the asymmetry drops drastically after 10 µs. When the background has been removed, we see the signal from the carbon contribution only, and there is minimal relaxation taking place, which has been shown to agree with [7]. The errors in the data increase significantly after around 10 µs which is a residual effect of having the long-lived background in the original data.…”

Muonic atom as an acceptor centre in diamond

“…The behaviour of the muon spin polarization in the reference graphite sample was studied at temperatures 9.6, 50, 100, 200, and 300 K in a magnetic field of 14 kOe. It was observed that in graphite the muon spin polarization and the frequency of the muon spin precession do not depend on temperature: [P 0 (T ) − P 0 (300 K)]/P 0 (300 K) 0.06 ± 0.08 and [ω(T ) − ω(300 K)]/ω(300 K) (6 ± 4) · 10 −5 (see also [13]). The relaxation of the muon spin in graphite was not observed within the accuracy of the measurements (R < 0.05 MHz).…”

“…The muon polarization P 0 in the 1s state of copper is close to zero due to the hyperfine interaction of the muon spin with the spin of the nucleus and due to very fast transitions between the levels F + = I + S µ and F − = I − S µ , where I is the spin of the copper nucleus and S µ is the muon spin (see [11,12,13]).…”

Search for magnetic ordered phase in Zn0.99Co0.01O compound using μSR method

“…Δt was 0.625 ns in these measurements. The mea surement method and procedure of restoration of the muon spin polarization function P i (t) from the μ -SR spectra were described in detail in [30,31].…”