Selective magneto‐luminescence spectroscopy of donoacceptor pairs in n‐GaAs

Abstract

The results of selective magneto-luminescence measurements of donor -acceptor pairs in n-type GaAs are discussed. The experimental data are compared with the calculated energy levels of a hydrogen-like atom in a magnetic field, enabling us to identify a large number of high angular momentum states of the hydrogen-like impurity in magnetic fields. It is shown that in addition to intra-donor transitions, the spin-flip excitations of donor -acceptor pairs involving heavy and light holes can be observed, yielding information about g-factors for heavy and light holes. For the pairs with separations smaller than the donor Bohr radius, a strong modification of the SPL spectrum is observed. This effect is discussed in terms of modification of the acceptor ground state induced by the interaction with a neighbouring donor centre.

Magnetized Plasma in Polar Semiconductors

“…The additional transitions which are observed in the spectra at high magnetic field are attributed to the Raman scattering signals related to the excitations between the 1s ground state and the excited states of electrons frozen on donor states. The I-D line is assigned to the 1s−2p 0 transition, which is active in the Raman scattering processes and usually observed in experiments on insulating n-type semiconductors [25]. The E + and E − peaks are most likely associated with the 1s−2p + transition in the region, where it splits due to the resonant magnetopolaron effect [26].…”

“…A similar system was already used for selective excitation of donor acceptor-pair luminescence in GaAs, in which the high rejection rate of the laser light and Raman signal from the fiber is also important [25]. The experiments were performed in magnetic fields up to 28 T at liquid nitrogen (T = 77 K) and helium (4.2 K) bath temperatures, in a backscattering geometry: the wave vector k i of the incident light anti-parallel to the wave vector k s of the scattered light.…”

Electronic structure of shallow impurities in GaN studied via bound exciton magnetooptics

“…We would like to mention two examples of such experimental methods, both related to studies of donors in GaAs. The first one, selective magneto-luminescence spectroscopy of donor-acceptor pairs, allows to resolve a rich spectrum of the donor excitations [8], in consequence of the relaxed selection rules, due the presence of the axial electric field. Another method consist of measuring transitions related to the neutral-donor bound-exciton recombination.…”