Abstract
This study was undertaken to investigate the potential advantages of certain rare‐earth elements as n‐type dopants for lead chalcogenide diode lasers grown by molecular beam epitaxy. It was found that holmium (Ho), dysprosium (Dy), and erbium (Er) are n‐type dopants in PbTe, producing maximum electron concentrations of 1×1019 cm3 at 77 K. However, annealing under tellurium‐rich conditions caused PbTe samples doped with these elements to convert to p‐type under some annealing conditions. The diffusion coefficient of Ho in PbTe at 370 °C is less than 1×1016 cm2/s at high concentration (>1×1018 cm3). At low concentration (∼1017 cm3), fast diffusing Ho was observed. Significant degradation of contacts to Ho‐, Dy‐, and Er‐doped PbTe was observed after prolonged aging.