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arXiv · 2105.11894

Microscopic processes during ultra-fast laser generation of Frenkel defects in diamond

Benjamin Griffiths·Andrew Kirkpatrick·Shannon S. Nicley·Rajesh L. Patel·Joanna M. Zajac·Gavin W. Morley·Martin J. Booth·Patrick S. Salter·Jason M. Smith
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Abstract

Engineering single atomic defects into wide bandgap materials has become an attractive field in recent years due to emerging applications such as solid-state quantum bits and sensors. The simplest atomic-scale defect is the lattice vacancy which is often a constituent part of more complex defects such as the nitrogen-vacancy (NV) centre in diamond, therefore an understanding of the formation mechanisms and precision engineering of vacancies is desirable. We present a theoretical and experimental study into the ultra-fast laser generation of vacancy-interstitial pairs (Frenkel defects) in diamond. The process is described by a set of coupled rate equations of the pulsed laser interaction with the material and of the non-equilibrium dynamics of charge carriers during and in the wake of the pulse. We find that a model for Frenkel defect generation via the recombination of a bound biexciton as the electron plasma cools provides good agreement with experimental data, reproducing an effective non-linearity of $\sim$ 40 for Frenkel defect generation with respect to laser pulse energy.

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Benjamin Griffiths, Andrew Kirkpatrick, Shannon S. Nicley, Rajesh L. Patel, Joanna M. Zajac, Gavin W. Morley, Martin J. Booth, Patrick S. Salter, Jason M. Smith. 2021-05-25. Microscopic processes during ultra-fast laser generation of Frenkel defects in diamond. https://doi.org/10.1103/physrevb.104.174303

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