Next generation wound care technology capable of diagnosing wound parameters, promoting healthy cell growth and reducing pathogenic infections noninvasively would provide patients with an improved standard of care and an accelerated wound repair mechanism. Temperature is one of the indicating biomarkers specific to chronic wounds. This work reports a hybrid, multifunctional optical material platform -nanodiamond-silk membranes as bioinspired dressings capable of temperature sensing and wound healing. The hybrid structure was fabricated through electrospinning and formed 3D sub-micron fibrous membranes with high porosity. The silk fibres are capable of compensating for the lack of extracellular matrix at the wound site, supporting the wound healing process. The negatively charged nitrogen vacancy (NV -) color centres in nanodiamonds (NDs) exhibit optically detected magnetic resonance (ODMR) properties and act as fluorescent nanoscale thermometers, capable of sensing temperature variations associated to the presence of infection or inflammation in a wound, without physically removing the dressing. Our results show that the presence of NDs in the hybrid ND-silk membranes improve the thermal stability of silk fibres. The NVcolor centres in NDs embedded in silk fibres exhibit well-retained fluorescent and ODMR properties. Using the NVcentres as fluorescent nanoscale thermometers, we achieved temperature sensing at a range of temperatures, including the biologically relevant temperature window, on cellcultured ND-silk membranes. An enhancement in the temperature sensitivity of the NVcentres was observed for the hybrid materials. The hybrid membranes were further tested in vivo in a murine wound healing model and demonstrated biocompatibility and equivalent wound closure rates as the control wounds. Additionally, the hybrid ND-silk membranes showed selective antifouling and biocidal propensity toward Gram-negative Pseudomonas aeruginosa and Escherichia coli, while no effect was observed on Gram-positive Staphylococcus aureus.

We report on a high-power third-order dispersion managed amplification system that delivers 33-fs pulses of 93.5 W at a repetition rate of 55 MHz. A pair of grisms are used as the pre-chirper for optimizing the third order dispersion (TOD) to group velocity dispersion (GVD) ratio. Detail experiments show that the use of a grsim pre-chirper significantly enhances the quality of the compressed pulses. We demonstrate that the third order dispersion of both the amplifier and the compressor can be compensated for by the grisms. Furthermore, the nonlinear phase shift introduced by spectral asymmetry during amplification can be restrained. This type of scheme, applied in our experiment, can be used for further development of a high power laser with ultrashort pulse and wide spectrum.

Diamond containing the negatively charged nitrogen-vacancy (NV) center is emerging as a significant new system for magnetometry. However, most NV sensors require microscopes to collect the fluorescence signals and are therefore limited to laboratory settings. By incorporating micron-scale diamond particles at an annular interface within the cross section of a silicate glass fiber, a high-sensitivity and robust fiber platform for magnetic field sensing is demonstrated here. The fluorescence and spin properties of NV centers embedded in the diamond crystals are well preserved during the fiber drawing process, leading to enhanced continuous-wave diamond-magnetometry in fiber-transmitted sensing configurations. The interface doping of diamond particles also leads to reduced fiber propagation loss and benefits the guidance of NV-fluorescence in the hybrid fiber. Using the diamond-fiber system, magnetic field readout through 50 cm of fiber is achieved. This study paves the way for novel fiber-based diamond sensors for field-deployable quantum metrology applications.

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We experimentally explored the influence of passive harmonic mode locking on the temporal and spectral features of a ytterbium-doped fiber laser. Similar dependences of free-running linewidth of the laser carrier-envelope offset frequency (f0) on the intracavity net dispersion were observed for the fundamental-, second-, and third-order mode-locking states. Due to the reduction of nonlinear effects and supermode phase locking that balanced the third-order dispersion in the fiber cavity, the third-order harmonic mode-locking exhibited the narrowest free-running f0 linewidth of ~120 kHz in the near-zero net dispersion regime.