QR code micro-certified gemstones: femtosecond writing and Raman characterization in Diamond, Ruby and Sapphire
Tipo
Artigo
Data de publicação
2019
Periódico
Scientific Reports
Citações (Scopus)
9
Autores
Batista A.J.
Vianna P.G.
Ribeiro H.B.
Matos C.J.S.
Gomes A.S.L.
Vianna P.G.
Ribeiro H.B.
Matos C.J.S.
Gomes A.S.L.
Orientador
Título da Revista
ISSN da Revista
Título de Volume
Membros da banca
Programa
Resumo
© 2019, The Author(s).This paper reports on a micro-certification procedure using femtosecond laser irradiation to microscopically mark a single-crystalline gemological and natural diamond, synthetic ruby and synthetic sapphire, inscribing a QR Code on them. The QR-code was composed of a set of 25 × 25 micropoints, and the irradiation energy was optimized at 1kHz repetition rate. The code was made at a 20 µm relative depth into the gemstone surfaces by controlling the incident laser energy, that was set to 3 μJ for all the samples. Characterization by optical and electron microscopy, as well as micro-Raman hyperspectral imaging showed that the microdots have a diameter of about 14 µm perpendicular to the irradiation direction, being laterally spaced by 14 µm-18 µm applied for each sample. This work corroborates the feasibility of using ultrafast laser inscription technology to fabricate microdots with great quality on gemstone surfaces, which offers a great potential for the jewelry industry to safely micro-encrypt gemological certifications. The compositional and morphological characterization of the modified surface was carried by micro-Raman spectroscopy and scanning electron microscopy.