Properties of GaP Studied over 50 Years

Abstract

A unique set of GaP semiconductor samples studied for over 50 years has exhibited significant improvement in their properties through the formation of the perfect host crystal lattice and the N-impurity crystal superlattice. This chapter reviews this evolution of properties and discusses their novel utility in advanced optoelectronic devices. More specifically, nitrogen-doped gallium phosphide (GaP:N) crystals that were originally prepared in the 1960s were theorized to form an excitonic crystal (1970s), and the best methods of their bulk, film, and nanoparticle crystal growth have subsequently been developed. The excitonic crystals yield novel and useful properties including enhanced stimulated emission and very bright and broadband luminescence at room temperature, which have been observed. These results provide a new approach to the selection and preparation of "perfect" materials for optoelectronics and offer a unique opportunity to realize a new form of solid-state host-the excitonic crystal-as a high-intensity light source with low thresholds for nonlinear optical effects.

Excitons and the Positronium Negative Ion: Comparison of Spectroscopic Properties

“…The role and application of bound excitons in nanoscience and technology have been discussed in the article of Pyshkin and Ballato [104]. This investigation [104] observes something like neutral shortlived atom analog-a particle consisting of heavy negatively charged nucleus (N atom with captured electron) and a hole.…”

“…The role and application of bound excitons in nanoscience and technology have been discussed in the article of Pyshkin and Ballato [104]. This investigation [104] observes something like neutral shortlived atom analog-a particle consisting of heavy negatively charged nucleus (N atom with captured electron) and a hole. Using bound excitons as short-lived analogs of atoms and sticking to some specific rules, Pyshkin and Ballato have been able to create a new solid-state media-consisting of short-lived nanoparticles excitonic crystal, obviously, with very useful and interesting properties for application in optoelectronics, nanoscience, and technology.…”

Introductory Chapter: Bound Excitons in Gallium Phosphide

“…We have been growing and exploring gallium phosphide [1][2][3][4][5][6][7][8] for more than a half a century, a process of experimenting, analysis and observation which resulted in unique material reflecting previously unexplored properties of excitons and new prospects for the use of GaP, which could be very interesting for application in the electronic industry.…”

“…In this way, decades pass before the lattice component occupies the exactly correct position in the crystal lattice, diffusing inside it at the storage temperature, from the place where it was at the time of the onset of cooling of a mixture of GaP, necessary for the onset of deposition and further growth of pure or doped crystals (see details in [1][2][3][4][5][6][7][8]). Naturally, most crystal manufacturers are reluctant to wait for improvements in the structure and properties of imperfect crystals, as this process is extremely slow.…”

“…Substitution period is equal to the Bohr diameter of exciton (~100 Å), and optical excitation is enough for complete saturation of the N sublattice with nonequilibrium electron-hole pairs (see details in Ref. [8]). …”