Infrared Donor-Acceptor Pair Spectra Involving the Deep Oxygen Donor in Gallium Phosphide

Abstract

We report the infrared radiative recombination of electrons bound to deep O donors with holes bound to C, Zn, or Cd acceptors in GaP. From the transition energies of the discrete no-phonon lines, which can be closely accounted for using a simple Coulomb donor-acceptor interaction energy term, the ionization energy of the O donor is calculated to be 893±2 meV. Aggregation between Zn (or Cd) acceptors and O donors in nearest-neighbor lattice sites produces strong red luminescence not observed in C-doped crystals where the closest possible donor-acceptor pairs are next-nearest neighbors. The infrared pair spectra are broad because of strong phonon-assisted transitions arising from the tight binding of the O donor. Two modes of energy 19.5 and 47.0 meV are prominent in the infrared spectra, whereas only one ^48-meV mode is prominent in the green luminescence due to recombinations between shallow donors and C, Zn, or Cd acceptors in GaP.

Electron Capture into the Two-ElectronO−State in GaP

“…An indication that the original one-electron interpretation of the DH data is incorrect is given by a comparison of the shape of the phonon replica structure in the luminescence spectrum of DH with that of the donor-acceptor (D-A) pair spectra of Dean, Henry, and Frosch, 7 [\ x = 1.65 and X 2 = l.l] which fit the pair (emission) spectra also explain the shape and temperature dependence of the photoneutralization (absorption) spectra for the O 0 ground state. [These are referred to as the configuration-coordinate (C-C) modes.]…”

High performance III-V photoelectrodes for solar water splitting via synergistically tailored structure and stoichiometry

“…2c, the Ga 2p 5/2 peaks with binding energies of 1118.0 and 1116.7 eV observed from bare GaInP 2 correspond to 3+ oxidation states for Ga 2 O 3 and GaInP 2 , respectively. Notably, the integrated area of Ga–O peak, reflecting the relative amount of Ga–O bonding, substantially increased after the dry etching, suggesting the incorporation of oxygen atoms at the etched surface of GaInP 2 and generation of defect states within the bandgap that can act as centers for non-radiative carrier recombination 33,34 . With similar origins, the relative amount of P–O (In–O) peaks increased over P–Ga (In–P) peaks after the formation of nanopillars by dry etching (Fig.…”

On the importance of antimony for temporal evolution of emission from self-assembled (InGa)(AsSb)/GaAs quantum dots on GaP(001)

“…A1, complicating a proper extraction of the background signal for individual wavelengths and correct time-constant extraction. This issue is overcome in TDPL by disentangling individual transitions by line-shape model fitting, where the slowest decay is assigned to (mainly nonradiative) pair recombination processes of donor-acceptor pairs (DAP) in GaP [42,43].…”

“…To describe the full PL spectrum, two additional Gaussian profiles are necessary. One of them describes a rather broad band (FWHM larger than 35 meV), clearly observable only at very low excitation powers, likely originating in the donor-acceptor pair (DAP) transitions in GaP [42,43] or other defect induced during GaAs IL and QDs formation (the latter in the case of samples with QDs). We attribute the second Gaussian band to the recombination from QDs, being due to non-optimized excitation wavelength, and thus very weak and observable mainly for high excitation powers.…”

“…Note, that τ 1 process decays rather slowly and does not completely disappear in one temporal window, therefore we take into account its repumping from previous pulses in TRPL fits, as discussed in the appendix. This issue is overcome in TDPL by disentangling individual transitions by lineshape model fitting, where the slowest decay is assigned to (mainly non-radiative) pair recombination of DAP in GaP [42,43]. Moreover, in spectral dependence for the evaluation of τ 1 we need to extend the model ( 4) by an additional contribution, likely connected with other defects created during the epitaxial growth process.…”