scholarly journals Microring Zone Structure for Near-Field Probes

Coatings ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1363
Author(s):  
Patrik Micek ◽  
Dusan Pudis ◽  
Peter Gaso ◽  
Jana Durisova ◽  
Daniel Jandura
Keyword(s):  
Time Domain ◽  
Finite Difference Time Domain ◽  
Near Field ◽  
Depth Of Field ◽  
Zone Structure ◽  
New Approach ◽  
Fdtd Simulations ◽  
Scanning Optical Microscopy ◽  
Near Field Scanning ◽  
Difference Time

Recent advances in Surface Plasmon Resonance (SPR) technologies have shown the possibility of transmission enhancement of localized modes propagating through sub-diffraction wide slits and apertures, resulting in the strong near-field focusing of metallic planar nanostructures. This work presents a new approach to the fabrication of high-resolution near-field optical probes using 3D lithography in combination with numerical finite difference time domain (FDTD) simulations. A narrow 500 nm depth of field focus area was observed both by numerical analysis and near field scanning optical microscopy (NSOM) measurements. Further research and optimization are planned in order to achieve subwavelength focal regions and increased signal intensities.

Three-Dimensional Finite-Difference Time-Domain Method Modeling of Nanowire Optical Probe

2014 ◽  
Vol 602-605 ◽  
pp. 3359-3362
Author(s):  
Chun Li Zhu ◽  
Jing Li
Keyword(s):  
Finite Difference ◽  
Time Domain ◽  
Finite Difference Time Domain ◽  
Incident Light ◽  
Near Field ◽  
Three Dimensional ◽  
Polarization Direction ◽  
Near Field Imaging ◽  
Difference Time ◽  
Field Imaging

In this paper, output near fields of nanowires with different optical and structure configurations are calculated by using the three-dimensional finite-difference time-domain (3D FDTD) method. Then a nanowire with suitable near field distribution is chosen as the probe for scanning dielectric and metal nanogratings. Scanning results show that the resolution in near-field imaging of dielectric nanogratings can be as low as 80nm, and the imaging results are greatly influenced by the polarization direction of the incident light. Compared with dielectric nanogratings, metal nanogratings have significantly enhanced resolutions when the arrangement of gratings is perpendicular to the polarization direction of the incident light due to the enhancement effect of the localized surface plasmons (SPs). Results presented here could offer valuable references for practical applications in near-field imaging with nanowires as optical probes.

STUDY ON A SORT OF CONTROLLABLE NONLINEAR LEFT-HANDED MATERIALS

2009 ◽  
Vol 18 (03) ◽  
pp. 441-456 ◽  
Author(s):  
HONG XIN ZHANG ◽  
LAN ZHAO ◽  
YING HUA LU
Keyword(s):  
Resonance Frequency ◽  
Time Domain ◽  
Material Properties ◽  
Finite Difference Time Domain ◽  
Transmission Properties ◽  
The Past ◽  
Left Handed ◽  
High Harmonics ◽  
Fdtd Simulations ◽  
Difference Time

In this paper, three kinds of controllable nonlinear left-handed materials (DNLHMs) are proposed and analyzed, which are designed by introducing inductors and capacitors into the traditional nonlinear left-handed materials (NLHMs) as inhomogeneous doped elements. Due to such changes, several new transmission properties have been presented through finite-difference time-domain (FDTD) simulations. These have brought new features to our DNLHMs. On one hand, the original passband in the traditional nonlinear left-handed material is narrowed after introducing inductors. In addition, a new passband, which does not exist in doped linear LHMs, is generated. On the other hand, through introducing capacitors, the original passband of the nonlinear left-handed material can be shifted, resonance frequency can be changed, and a new passband can be generated. When capacitors and inductors are introduced simultaneously, the material properties, such as the number of passbands, the characteristic resonance frequency, and the bandwidth, can also be changed. Noting these characteristics, the values of the introduced inductors and capacitors are varied to investigate the spectrum changes of DNLHMs. Then, a series of controllable properties of the DNLHMs can be retrieved. And more importantly, the designed DNLHMs give the adjustability of suppressing high harmonics, which is not possible in the past materials.

Localized Light Focusing and Super Resolution Readout via Chalcogenide Thin Film

2006 ◽  
Vol 918 ◽  
Author(s):  
Junji Tominaga ◽  
Paul Fons ◽  
Takayuki Shima ◽  
Kazuma Kurihara ◽  
Takashi Nakano ◽  
...  
Keyword(s):  
Finite Difference Time Domain ◽  
Near Field ◽  
Super Resolution ◽  
Spot Size ◽  
Optical Disc ◽  
Chalcogenide Film ◽  
Fdtd Simulations ◽  
Light Focusing ◽  
Difference Time ◽  
Chalcogenide Thin Film

AbstractWe have demonstrated that certain chalcogenide layers within a spinning super-RENS optical disc allow to squeeze the 650 nm laser beam to a spot size as fine as 50 nm using a 15-nm chalcogenide film. The near-field light was focused at a depth of just over 30 nm after passing through a chalcogenide film. Finite-difference time-domain (FDTD) simulations also reproduced these results. We suggest that a conductive ring aperture generated in the chalcogenide layers plays an important role in the localized light focusing.

Sign in / Sign up

Export Citation Format

Share Document