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This study focuses on the buckling behavior of composite microshells inside pacemakers to select the most durable material. Due to the strong electromagnetic forces encountered by pacemaker microshells, comprehensive research is needed to identify suitable materials. This study analyzes the buckling behavior of a porous sandwich cylindrical microshell attached to electrodes, which is supported by an elastic foundation and reinforced with functionally graded carbon nanotubes. Three porosity models are considered for the core material, and the equilibrium equations are derived using Hamilton's principle based on third order shear deformation theory. This study compares the critical buckling loads with those from the literature and examines the effects of various parameters, such as thickness stretching and non-stretching. The findings indicate that the thickness stretching effect has a significant influence on the critical buckling load. In addition, a lower functionally graded power index and higher porosity volume fraction result in higher critical buckling loads. These results are relevant for micro-electromechanical systems and can aid in the selection of appropriate materials for pacemaker microshells to improve their durability and performance. [ABSTRACT FROM AUTHOR]

Boron nitride nanoscrolls (BNSs) are open-ended, one-dimensional nanostructures made by the process of rolling boron nitride nanosheets into a scroll-like morphology. BNSs offer a high surface area to volume ratio and possess many unique properties (similar to carbon nanotubes, carbon nanoscrolls, and boron nitride nanotubes) such as high resistance to oxidation, chemical stability, increased lubrication, high-temperature resistance, electrical insulation, the ability to cap molecules inside and at the ends, and a wide bandgap regardless of chirality. Despite these attractive features and properties well suited for applications in biotechnology, energy storage, and electronics, the true potential of boron nitride and BNS as the next "miracle material" is yet to be fully explored. In this critical review, we assess, for the first time, various studies published on the formation and structural and dynamic characteristics of BNS; potential routes for BNS synthesis; and the toxicology of BNS. Finally, the future perspectives of BNS are discussed in view of its unique and exceptional candidacy for many (real-world) applications. [ABSTRACT FROM AUTHOR]

We report soliton rains in a tunable Tm-doped fiber laser mode locked by carbon nanotubes. We also detect their second- and third-harmonics. We achieve a tunability of over 56 nm, from 1877 to 1933 nm, by introducing a polarization-maintaining isolator and two in-line polarization controllers. This makes our system promising as a tunable filter for ultrafast spectroscopy. [ABSTRACT FROM AUTHOR]

We report dissipative soliton generation from an Yb-doped all-fiber nonlinearity- and dispersionmanaged nanotube mode-locked laser. A simple all-fiber ring cavity exploits a photonic crystal fiber for both nonlinearity enhancement and dispersion compensation. The laser generates stable dissipative solitons with large linear chirp in the net normal dispersion regime. Pulses that are 8.7 ps long are externally compressed to 118 fs, outperforming current nanotube-based Yb-doped fiber laser designs. [ABSTRACT FROM AUTHOR]

Ultrafast laser inscription is used to fabricate the gain element for a mode-locked Er-doped bismuthate glass waveguide laser. Mode-locking is initiated and stabilized by the use of a single wall carbon nanotube saturable absorber. The waveguide laser produces 320 fs pulses at 1.56 μm with a pulse repetition rate of 40 MHz and average output power of 1.25 mW. [ABSTRACT FROM AUTHOR]

We report ultrafast highly chirped pulses from an erbium doped, nanotube-mode-locked fiber oscillator. We generate 1.6 W average power and 11 kW peak power by seeding a fiber amplifier. This paves the way to mode-locked all-fiber master oscillator amplifiers as economic and compact sources for high-power applications, such as micromachining and laser surgery. [ABSTRACT FROM AUTHOR]

We present an evanescent-field device based on a right-angled waveguide. This consists of orthogonal waveguides, with their points of intersection lying along an angled facet of the chip. Light guided along one waveguide is incident at the angled dielectric-air facet at an angle exceeding the critical angle, so that the totally internally reflected light is coupled into the second waveguide. By depositing a nanotube film on the angled surface, the chip is then used to mode-lock an Erbium doped fiber ring laser with a repetition rate of 26 MHz, and pulse duration of 800 fs. [ABSTRACT FROM AUTHOR]