B. Maleyre

Indium nitride quantum dots grown by metalorganic vapor phase epitaxy

With respect to growing indium nitride quantum dots with very low surface densities for quantum cryptography applications, we have studied the metalorganic vapor phase epitaxy of InN onto GaN buffer layers. From lattice mismatch results the formation of self-assembled dots. The effects of the growth temperature, V/III molar ratio, and deposition time are studied, and we demonstrate that quantum-sized dots of InN can be grown with a material crystalline quality similar to the quality of the GaN buffer layer, in densities of 107 to 108 cm−2. Such low densities of dots allow for the realization of experiments or devices in which a single dot is isolated, and may be used in the near future to produce single-photon sources.With respect to growing indium nitride quantum dots with very low surface densities for quantum cryptography applications, we have studied the metalorganic vapor phase epitaxy of InN onto GaN buffer layers. From lattice mismatch results the formation of self-assembled dots. The effects of the growth temperature, V/III molar ratio, and deposition time are studied, and we demonstrate that quantum-sized dots of InN can be grown with a material crystalline quality similar to the quality of the GaN buffer layer, in densities of 107 to 108 cm−2. Such low densities of dots allow for the realization of experiments or devices in which a single dot is isolated, and may be used in the near future to produce single-photon sources.

Radiative and nonradiative recombination processes in InN films grown by metal organic chemical vapor deposition

The 800meV photoluminescence band in indium nitride is excited under pulsed excitation conditions and is investigated as a function of temperature and time. Our results are consistent with a composite photoluminescence feature composed of two overlapping bands separated by an ∼10meV splitting, with populations described by a thermal equilibrium model. Efficient nonradiative recombination channels rule both the temperature dependence of the time-integrated photoluminescence spectra and the recombination dynamics. At 10K, the radiative recombination time is of the order of 300ns, while the nonradiative recombination time, which is ruled by activation energy of 8meV, is about 100ps.