146 research outputs found
Nano-imaging with TiO2 superlenses: A comparative study of Design variants
We evaluate and compare the super-resolution imaging performances of different TiO2 superlens designs (hemisphere, super-hemisphere, and full spheres) in wide-field and confocal modes. Our findings are important for many super-resolution application
Superlens-Assisted Laser Nanostructuring of Long Period Optical Fiber Gratings (LPGs) for Enhanced Refractive Index Sensing
We present an innovative method to enhance Long Period Optical Fiber Gratings
(LPGs) for refractive index sensing using microsphere-assisted superlens laser
nanostructuring. This technique involves self-assembling a silica microsphere
monolayer on LPGs' outer surface, followed by pulsed laser irradiation to
generate nanoholes (300-500 nm) forming nanohole-structured LPGs (NS-LPGs). In
experiments, two nanohole densities were compared for their impact on sensing
performance in sucrose and glycerin solutions. The nanostructured NS-LPGs
showed improved sensitivity by 16.08% and 19.57% compared to regular LPGs, with
higher nanohole density yielding greater enhancement. Importantly, the
permanent nanohole structures ensure durability in harsh environments,
surpassing conventional surface-coating-based LPGs. Further improvements can be
achieved by refining nanostructuring density and controlling nanohole size and
depth. Our work represents a notable advancement in LPG sensor engineering,
prioritizing surface nanostructuring over nano-coating, promising enhanced
refractive index sensing applications.Comment: 13 pages, 5 figure
Surface plasmon resonance assisted rapid laser joining of glass
Rapid and strong joining of clear glass to glass containing randomly distributed embedded spherical silver nanoparticles upon nanosecond pulsed laser irradiation (∼40 ns and repetition rate of 100 kHz) at 532 nm is demonstrated. The embedded silver nanoparticles were ∼30–40 nm in diameter, contained in a thin surface layer of ∼10 μm. A joint strength of 12.5 MPa was achieved for a laser fluence of only ∼0.13 J/cm2 and scanning speed of 10 mm/s. The bonding mechanism is discussed in terms of absorption of the laser energy by nanoparticles and the transfer of the accumulated localised heat to the surrounding glass leading to the local melting and formation of a strong bond. The presented technique is scalable and overcomes a number of serious challenges for a widespread adoption of laser-assisted rapid joining of glass substrates, enabling applications in the manufacture of microelectronic devices, sensors, micro-fluidic, and medical devices
Enhancing Security with Superlens-Enabled Laser Direct Marking of Anti-counterfeiting DotCode
We report a novel anti-counterfeiting laser marking technology based on superlens- assisted nanoscale marking of 2D Dotcodes, which replaces conventional TEXT or other 2D code schemes for enhanced security
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