Laser Applications in Microelectronic and Optoelectronic Manufacturing (LAMOM) XXXI in SPIE. Photonics West 2026（サンフランシスコ、アメリカ）にて、宮地研の研究成果を2件発表します。宮地は本会議のCo-Chairです。

[13880-39] Formation process of nitrogen-vacancy centers in diamonds by sub-10 femtosecond laser pulses

Author(s): Kazuma Ishide, Tokyo Univ. of Agriculture and Technology (Japan); Aiko Narazaki, National Institute of Advanced Industrial Science and Technology (Japan); Godai Miyaji, Tokyo Univ. of Agriculture and Technology (Japan)

20 January 2026 • 6:00 PM - 8:00 PM PST | Poster Hall (Moscone West, Level 2)

Abstract: We report the formation process of nitrogen-vacancy (NV) centers in diamonds by using laser pulses with a pulse duration of 7 fs. The pulses were focused onto the diamond surfaces with a reflective objective mirror. The photoluminescence (PL) mapping showed a three-fold increase in PL intensity in the laser-irradiated area. Furthermore, the PL spectra showed an increase of zero-phonon line (ZPL) of NV0 and a ZPL of NV–, while the Raman spectra showed no change of the bonding structure from sp3 to sp2. These results indicate that NV centers can be created in diamonds without graphitization by using 7-fs laser pulses.

[13880-42] Controlling spatial distribution of plasmonic near-fields on Si excited with a femtosecond laser pulse using a SiO2 film

Author(s): Yuto Iida, Godai Miyaji, Tokyo Univ. of Agriculture and Technology (Japan)

20 January 2026 • 6:00 PM - 8:00 PM PST | Poster Hall (Moscone West, Level 2)

Abstract: Plasmonic near-fields generated by intense femtosecond (fs) laser pulses can form periodic surface nanostructures. We irradiated the fs pulses on the silicon gratings with SiO2 films and observed their reflectivity and morphological changes of the surfaces as a function of the incident angle. The thickness of the SiO2 films altered the angle at which a clear dip in reflectivity appeared, while the morphological changes were consistent with the electromagnetic field distributions on the surface calculated with an RCWA method. These results demonstrate that the wavelength of the SPPs and the spatial distribution of the plasmonic near-fields can be controlled by varying the SiO2 film thickness.

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