Fast isochoric heating of a pre-compressed plasma core with a high-intensity short-pulse laser is an attractive and alternative approach to create ultra-high-energy-density states like those found in inertial confinement fusion (ICF) ignition sparks. Laser-produced relativistic electron beam (REB) deposits a part of kinetic energy in the core, and then the heated region becomes the hot spark to trigger the ignition. However, due to the inherent large angular spread of the produced REB, only a small portion of the REB collides with the core. Here, we demonstrate a factor-of-two enhancement of laser-to-core energy coupling with the magnetized fast isochoric heating. The method employs a magnetic field of hundreds of Tesla that is applied to the transport region from the REB generation zone to the core which results in guiding the REB along the magnetic field lines to the core. This scheme may provide more efficient energy coupling compared to the conventional ICF scheme.

3D metal printing and aerospace industry is an ideal combination where 3D metal printing offers unmatched advantages over the conventional method in terms of its rapid prototyping, rapid tooling, easy maintenance and repairs. With the provision and implementation of 3D metal printing onto aerospace sector, leading manufacturers are now enjoying great benefits as this exciting technology reduces the lead-time, increases production flexibility as well as cost-effective. However, we are now left with a big question: whether or not this 3D metal printing technology has arrived to its maximum capacity where the system operates with no flaw. Previous studies have shown that 3D metal printing is battling with its consistency, repeatability and traceability due to many independent variables that need to be controlled in a single run. Adoption of Artificial Intelligence onto the 3D metal printing has been viewed to be a promising step and therefore, serves as a cornerstone towards a better development of 3D metal printing technology.

A sensitive tapered optical fiber sensor incorporating graphene oxide (GO) and polyvinyl alcohol (PVA) composite film for the rapid measurement of changes in relative humidity was proposed and experimentally demonstrated. The sensing principle was based on the intensity modulation of the transmitted light induced by the refractive index changes of the sensitive coatings. The sensing region was obtained by tapering a section of single-mode optical fiber (SMF) from its original 125 µm diameter down to 9.03 µm. The tapered structure was then modified through deposition of GO/PVA nanocomposites by using the dip-coating technique. The field emission scanning electron microscope (FESEM) and Raman spectroscopy were used to characterize the structure of the composite film. As evidenced by a Fourier transform infrared spectroscopy (FTIR) analysis, the presence of oxygen functional groups (such as-OH and COOH) on the GO structure enabled the attachment of PVA molecules through hydrogen bonding and strong adhesion between GO/PVA layers. The performance of the sensor was tested over a wide range (20% RH to 99.9% RH) of relative humidity. The sensor showed a good response with its signal increasing linearly with the surrounding humidity. The tapered optical fiber sensor with the coating of GO/0.3 g PVA achieved the highest sensitivity [0.5290 RH (%)]. The stability, repeatability, reversibility, as well as response time of the designated sensor were also measured and analyzed.

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