Integrating Fluorescent Nanodiamonds into Polymeric Microstructures Fabricated by Two-Photon Polymerization

Abstract

Nitrogen-vacancy (NV) and other color centers in diamond have attracted much attention as non-photobleaching quantum emitters and quantum sensors. Since microfabrication in bulk diamonds is technically difficult, embedding nanodiamonds with color centers into designed structures is a way to integrate these quantum emitters into photonic devices. In this study, we demonstrate a method to incorporate fluorescent nanodiamonds into engineered microstructures using two-photon polymerization (2PP). We studied the optimal concentration of nanodiamonds in the photoresist to achieve structures with at least one fluorescent NV center and good structural and optical quality. Fluorescence and Raman spectroscopy measurements were used to confirm the presence and location of the nanodiamonds, while absorbance measurements assessed scattering losses at higher concentrations. Our results show the feasibility of fabricating microstructures embedded within fluorescent nanodiamonds via 2PP for photonics and quantum technology applications.

Active Optical Tuning of Azopolymeric Whispering Gallery Mode Microresonators for Filter Applications

“…A surface roughness of at most 15 nm was estimated with the SEM equipment's 3D analysis software, indicating that the resonators are suitable for applications in the near-infrared spectral region. The absorption spectrum of the doped photoresist, depicted in Figure 2, shows an absorption peak near 514 nm, a ributed to DR13 [40], and a broad transparency window in the near-infrared region, which is a known feature of this photoresist [41]. From the sample absorbance at 514 nm, we were able to determine the linear absorption coefficient of the resist as α = 1070 cm −1 .…”

“…Using FSR = , in which is the mode wavelength, is the resonator's radius, and is its index of refraction (considered here to be = 1.54), we determined that the FSR = 9.13 at 1530 nm, which is in good agreement with the observed experimental one. The absorption spectrum of the doped photoresist, depicted in Figure 2, shows an absorption peak near 514 nm, attributed to DR13 [40], and a broad transparency window in the near-infrared region, which is a known feature of this photoresist [41]. From the sample absorbance at 514 nm, we were able to determine the linear absorption coefficient of the resist as α = 1070 cm −1 .…”