Publisher Summary A refractive index can be increased by ion implantation by changes in density and structure, by the addition of high-polarizability impurity ions, by a reduction of the plasma effect that increases the index and that is most important in the wavelength region far from the energy gap, and by absorption changing in the index in the region of the gap, that is, via the Kramers–Kronig relation. This chapter discusses the optical properties of implanted semiconductors, electrooptic components formed by ion implantation, general principles that determine most luminescent systems, effects of implantation temperature, luminescence centers in LiF-Mg-Ti radiation dosimeters, and use of line spectra in defect studies. In the LiF system, the luminescence bands are broad, and if alternative versions of the same complex exist, they cannot be resolved from the spectra. The addition, by implantation, of ions with incomplete inner electron shells opens up new possibilities as the lattice distortions of the free-ion energy levels are strongly perturbed by the defects in the neighborhood of the ion.

Optical Effects of Ion Implantation

The main purpose of this article is to review our understanding of the predominant mechanism for defect creation in alkali halides i.e. the evolution of Frenkel (F-H) pairs from self-trapped excitons. Consideration is first given to other models of defect formation since they may play a secondary role in alkali halides and major roles in other solids. Recent experimental work is surveyed with emphasis on studies of non-radiative transitions from highly-excited self-trapped excitons, of F-centre formation and of the photochemical processes associated with impurities and with the surfaces of alkali halides. Brief descriptions are given of the photochemical process in silver halides and of recombination-induced defect migration in compound semiconductors. Finally a critical assessment is made of our understanding of the dominant mechanisms for defect formation in alkali halides with particular attention paid to the identification of the precursor state, the excited state of the self-trapped exciton ...

Creation of lattice defects by electronic excitation in alkali halides

Several methods are known for the evaluation of the main kinetic parameters related to a thermoluminescence (TL) curve, namely the activation energy, the pre-exponential factor and the kinetic order. These methods can easily be applied under certain conditions to a series of related thermally stimulated phenomena which are governed by similar differential equations. These include thermally stimulated conductivity (TSC), thermally stimulated electron emission (TSEE), ionic thermocurrent (ITC), derivative thermogravimetry (DTG), differential thermal analysis (DTA), thermal desorption and other phenomena. The similarities and differences between these phenomena are considered and the applicability of the various methods to the different cases is discussed.

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M. Saidoh

Papers

H-center interactions during thermal annealing in KBr