Materials Research and Technology

Biography

Biography: Nikolay Ledentsov

Abstract

Epitaxial quantum dots (QDs) resulted in multiple breakthroughs in physics of zero-dimensional structures and allowed advancements of optoelectronic devices. Most importantly, these tiny structures provided unique opportunities to modify and extend all basic principles of heterostructure lasers and light emitting diodes and extend their applications. The breakthrough occurred when techniques for self-organized growth allowed the fabrication of dense arrays of coherent islands, uniform in shape and size and simultaneously free from undesirable defects. The work on the development of the technology for such QDs contributed enormously to the progress in material science. First ever lasing at low and at room temperatures was achieved in self-organized QDs in 1993 (photo pumped, at equivalent current densities of 4 kA/cm2). At that time, the term quantum dots were not yet fully established and the 3D quantized structures were referred to as quantum clusters. Injection lasing was realized soon after. Since that time, a lot of progress has been made extending the wavelengths, performance and application ranges of QD lasers. Control over the processes during QD formation and application of post-QD-deposition defect reduction techniques were the keys in industrial device fabrication and also led to success in InGaN LEDs and InGaN lasers. Such techniques, protected by patents, are being broadly applied by industries now. Further progress in QDs allows developing of further novel approaches for QD fabrication and continuous improvement in the performance of QD-related devices.

Recent Publications

1. N.N. Ledentsov et al (1994) Optical properties of heterostructures with InGaAs-GaAs quantum clusters” Semiconductors 28, 832-834, submitted December 29th 1993.
2. A.Yu. Egorov et al. (1994) Effect of deposition conditions on the formation of (In,Ga)As quantum clusters in a GaAs matrix” Semiconductors 28, 809-811, submitted March 5th 1994.
3. N. N Ledentsov “Quantum dot laser“(2011) Semicond. Sci. Technol. 014001.
4. V. Shchukin, N. Ledentsov, and S. Rouvimov "Formation of Three-Dimensional Islands in Subcritical Layer Deposition in Stranski-Krastanow Growth" Phys. Rev. Lett. 110, 176101 (2013).
5. N. N. Ledentsov, V. A. Shchukin, M. V. Maximov, Yu. M. Shernyakov, A. S. Payusov, N. Yu. Gordeev and S. S. Rouvimov “High temperature laser diode based on a single sheet of quantum dots” Semicond. Sci. Technol. 30, 105005 (2015).