2026/03/11 by Chris Coutts, Christopher Coutts, Nicholas J. Sorensen +6
Materials Science · Physics and Astronomy · Engineering · #Diamond and Carbon-based Materials Research #Advanced Fiber Laser Technologies #Nonlinear Optical Materials Studies
paper · pdf · doi:10.1364/optica.597613
Diamond is a leading quantum photonics platform due to its ability to host qubits based on crystal defects such as nitrogen-vacancy centers. Fabricating nanophotonic devices from defect-rich diamond, which underpins many quantum sensing technologies, promises enhanced performance and integrability of diamond quantum sensors. Here, we demonstrate microdisk cavities fabricated from defect-rich diamond that support optical modes with high quality factor ( Q ∼7×10 4 at 1042 nm) and show that they exhibit saturable absorption. Power-dependent spectroscopy measurements spanning 979–1604 nm are used to observe intensity-dependent cavity loss and extract wavelength-dependent absorption coefficients and saturation intensities. At 1047 nm, we observe saturation and measure a saturation intensity of 3.3(1)MW/cm 2 2.1(8)MW/cm 2 and an absorption coefficient 0.53(2)cm −1 . These results provide insight into defect-mediated optical loss in diamond nanophotonics and suggest strategies to harness defect-induced nonlinearities in future diamond photonic devices.