Free‐to‐Bound Transitions in Lithium‐Doped Zinc Telluride

Publisher Website
Google Scholar
Abstract
The two no‐phonon emission lines at 2.336 eV ± 4 meV (A) and 2.362 eV ± 8 meV (B) characteristic of Li‐doped ZnTe at 4.2 K are studied as a function of temperature (4.2 < T < 300 K) and of impurity concentration (5 × 1016 to 5 × 1018cm−3). It is found that the energy of the B transition decreases linearly with the pone; 1/3 of the donor concentration. It is shown that this law is expected theoretically for free‐to‐bound transitions in a compensated p‐type semiconductor when the screening length is determined by the concentration of ionized impurities (Debye and Conwell model). The effect of doping on the temperature dependence of the intensity can be explained in terms of the previously proposed interpretation: conduction band‐to‐acceptor transition for the A‐line and donor‐to‐valence band transition for the B‐line.