Electronic structure of the phosphorus-vacancy complex in silicon: A resonant-bond model

Abstract

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Understanding the Jahn–Teller distortions for the divacancy and the vacancy–group-V-atom pair in silicon

“…Quantum mechanical treatments of periodic cells containing the defects by several groups using the local density approximation (LDA) have universally had difficulty in coming up with these results, predicting ''resonant bond'' distortions for the EPR-active charge states [5][6][7][8]. This has led to a challenge by the theorists involved as to whether the interpretation of the EPR results were correct.…”

A comprehensive theoretical picture of E centers in silicon: From optical properties to vacancy-mediated dopant diffusion

“…On the modelling side, the energy ranking of these configurations is not consistent between different studies [11][12][13][14][15][16] : the ground state geometry for the PV center was found to be a pairing configuration for both neutral and negative charge states in [11] (see also Ref. 12 for the neutral charge state) but a resonant one in [13].…”

“…However, Watkins speculated that their defect-induced optical bands should be very similar to AsV − . Even though the electronic structure of the E center is a clear evidence of the Jahn-Teller effect, no quantitative description has so far been given due to the limitations of previously used mean-field approaches [11][12][13][14][15][16] .…”

Simulation of the response of divacancy and As–V complex in silicon to external elastic strains

“…As a result, the symmetry of atomic relaxation pattern near a defect not necessarily reproduces the global lattice symmetry. Wellknown examples of this situation are met with divacancy [2,[4][5][6][7][8][9] and E-centres [1,10,11] in silicon. Moreover, sometimes the atomic potential energy surface can have more than one local minimum, corresponding to different relaxation patterns [9].…”