Refractive index variation in a free-standing diamond thin film induced by irradiation with fully transmitted high-energy protons.
Ion irradiation is a widely employed tool to fabricate diamond micro- and nano-structures for applications in integrated photonics and quantum optics. In this context, it is essential to accurately assess the effect of ion-induced damage on the variation of the refractive index of the material, both to control the side effects in the fabrication process and possibly finely tune such variations. Several partially contradictory accounts have been provided on the effect of the ion irradiation on the refractive index of single crystal diamond. These discrepancies may be attributable to the fact that in all cases the ions are implanted in the bulk of the material, thus inducing a series of concurrent effects (volume expansion, stress, doping, etc.). Here we report the systematic characterization of the refractive index variations occurring in a 38 µm thin artificial diamond sample upon irradiation with high-energy (3 MeV and 5 MeV) protons. In this configuration the ions are fully transmitted through the sample, while inducing an almost uniform damage profile with depth. Therefore, our findings conclusively identify and accurately quantify the change in the material polarizability as a function of ion beam damage as the primary cause for the modification of its refractive index.
Department of Physics and Astronomy, University of Firenze, Firenze, Italy.|Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Firenze, Firenze, Italy.
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Lagomarsino
Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Firenze, Firenze, Italy.
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S
Calusi
Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Firenze, Firenze, Italy.
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0000-0002-0199-9296
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Massi
Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Firenze, Firenze, Italy.
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Gelli
Department of Physics and Astronomy, University of Firenze, Firenze, Italy.|Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Firenze, Firenze, Italy.
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Sciortino
Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Firenze, Firenze, Italy.
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Taccetti
Department of Physics and Astronomy, University of Firenze, Firenze, Italy.|Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Firenze, Firenze, Italy.
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Giuntini
Istituto Nazionale di Ottica (INO), CNR, Firenze, Italy.
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Sordini
Istituto Nazionale di Ottica (INO), CNR, Firenze, Italy.|European XFEL GmbH, Hamburg, Germany.
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0000-0002-2768-4559
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Vannoni
Physics Department and NIS Inter-departmental Centre, University of Torino, Torino, Italy.|Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Torino, Torino, Italy.|Consorzio Nazionale Interuniversitario per le Scienze fisiche della Materia (CNISM), Sezione di Torino, Torino, Italy.
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Bosia
Physics Department and NIS Inter-departmental Centre, University of Torino, Torino, Italy.|Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Torino, Torino, Italy.|Consorzio Nazionale Interuniversitario per le Scienze fisiche della Materia (CNISM), Sezione di Torino, Torino, Italy.
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Monticone
Physics Department and NIS Inter-departmental Centre, University of Torino, Torino, Italy. paolo.olivero@unito.it.|Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Torino, Torino, Italy. paolo.olivero@unito.it.|Consorzio Nazionale Interuniversitario per le Scienze fisiche della Materia (CNISM), Sezione di Torino, Torino, Italy. paolo.olivero@unito.it.
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0000-0002-7512-6295
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Olivero
School of Physics, University of Melbourne, Melbourne, Australia.|Royal Melbourne Institute of Technology (RMIT), Melbourne, Australia.
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BA
Fairchild
School of Physics, University of Melbourne, Melbourne, Australia.
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Kashyap
School of Physics, University of Melbourne, Melbourne, Australia.
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Alves
School of Physics, University of Melbourne, Melbourne, Australia.
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Strack
School of Physics, University of Melbourne, Melbourne, Australia.
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Prawer
Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, RMIT University, Melbourne, 3001, Australia.
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Greentree
D018130:Diamond / Q000737:chemistry* / Q000528:radiation effects*; D055620:Optical Phenomena; D055095:Optics and Photonics; D011522:Protons; D012031:Refractometry
D011522:Protons; D018130:Diamond