Dynamics of stimulated emission in silicon nanocrystals

Abstract

Time-resolved luminescence measurements on silicon nanocrystal waveguides obtained by thermal annealing of plasma-enhanced chemical-vapor-deposited thin layers of silicon-rich oxide have revealed fast recombination dynamics related to population inversion which leads to net optical gain. Variable stripe length measurements performed on the fast emission signal have shown an exponential growth of the amplified spontaneous emission with net gain values of about 10 cm−1. The fast emission component is strongly dependent on the pumping length for fixed excitation intensity. In addition, both the fast component intensity and its temporal decay revealed threshold behavior as a function of the incident pump intensity.

Ultraviolet optoelectronic devices based on AIGaN alloys grown by molecular beam epitaxy

“…[124][125][126][127][128] The reader is referred to the original papers by Pecora et al for the details of the measurements and data analysis. In here we only present a summary of these data.…”

Carbon Nanocrystal-Based Organic Thin-Film Transistors for Nonvolatile Memory Nanodevices

“…Nonvolatile memory devices are expected to be operated at a lower voltage and with higher integration than conventional floating-gate memories [3]. Nonvolatile memory devices made of silicon nanocrystal (nc-Si) and germanium nanocrystal (nc-Ge) embedded in/on an oxide layer have been fabricated by several techniques such as chemical vapor deposition (CVD) [4,5], using a molecular ion beam [6,7] and, recently, using a focused ion beam (FIB) [8]. The FIB was used because they enable the formation of nanocrystal dots by a focused gallium (Ga + ) ions that can be precisely irradiated at array positions of nanoscale order.…”

Quantum Confined Intense Red Luminescence from Large Area Monolithic Arrays of Mesoporous and Nanocrystal-Decorated Silicon Nanowires for Luminescent Devices

“…12 Recent developments in nanoscale silicon crystals that provide multiple exciton generation events (at energies greater than twice the bandgap) per incident photon may improve efficiencies. 13 Porous semiconductors and clusters of quantum dots, particularly of silicon, have also been the subject of intense research recently for Li-ion batteries [14][15][16] water oxidation 17 and electroluminescent devices 18 and those exhibiting optical gain, [19][20][21] and a range of (bio)sensors. 22,23 Since the discovery of visible light emission in porous silicon [24][25][26] that in the main, arose from quantum confinement effects, porous silicon has had some usefulness for nanoelectronic devices, 27 and field effect transistors.…”