Construction of femtosecond laser irradiation platform for creating quantum sensing devices

Ishino Masahiko, Thanhhung Dinh

Published Jul 24, 2024• 0 citations

Abstract

Nitrogen-vacancy (NV) centers in diamond are expected to be quantum sensing devices such as magnetic and electric fields, temperature, pressure and so on. The generation of NV centers by irradiations of femtosecond laser pulses has been reported. Femtosecond laser can write NV centers in diamond directly and this direct writing can realize a flexible spatial arrangement of NV centers. As the application of the laser system, we have constructed the femtosecond laser irradiation platform for creating the quantum sensing device, such as NV centers. The femtosecond laser pulse is focused on a sample surface by an objective lens and laser pulse intensity is controlled by attenuators. By use of this irradiation apparatus, we have irradiated diamond samples to create NV centers. We could confirm several graphitization spots, but the signal intensity from NV center did not exist. To use the irradiation platform for creating NV centers in diamond, it needs some improvement, more increasing the repetition rate of irradiation laser and/or impurity nitrogen density in diamond sample.

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