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arXiv · 2203.15505

Laser-Induced Graphitisation of Diamond Under 30 fs Laser Pulse Irradiation

Bakhtiar Ali·Han Xu·Dashavir Chetty·Robert T. Sang·Igor V. Litvinyuk·Maksym Rybachuk
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Abstract

The degree of laser-induced graphitisation from a sp3-bonded to a sp2-bonded carbon fraction in a single crystal chemical vapour deposited (CVD) diamond under a varying fluence of an ultrashort pulsed laser (30 fs, 800 nm, 1 kHz) irradiation has been studied. The tetrahedral CVD sp3-phase was found to transition to primarily an sp2-aromatic crystalline graphitic fraction below the critical fluence of 3.9 J/cm2, above which predominantly an amorphous carbon was formed. A fractional increase of fluence from 3.3 J/cm2 to 3.9 J/cm2 (~ 20 %) resulted in a substantial (~ three-fold) increased depth of the sp2-graphitised areas owing to the non-linear interactions associated with an fs-laser irradiation. Additionally, formation of C=O carbonyl group was observed below the critical threshold fluence; the C=O cleavage occurred gradually with the increase of irradiation fluence of 30 fs laser light. The implications for these findings on enhancement of fs-driven processing of diamond are discussed.

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Bakhtiar Ali, Han Xu, Dashavir Chetty, Robert T. Sang, Igor V. Litvinyuk, Maksym Rybachuk. 2022-03-25. Laser-Induced Graphitisation of Diamond Under 30 fs Laser Pulse Irradiation. https://doi.org/10.1021/acs.jpclett.2c00429

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