Nano-scale study of microstructure of Eu(DBM)3phen-doped poly(methyl methacrylate) by near-field scanning microscopy and optical properties

2004 ◽  
Vol 19 (8) ◽  
pp. 2256-2261 ◽  
Author(s):  
Hao Liang ◽  
Xiaohong Sun ◽  
Qijin Zhang ◽  
Hai Ming ◽  
Jianhua Cao ◽  
...  
Keyword(s):  
Optical Properties ◽  
Fluorescence Spectra ◽  
Doping Concentration ◽  
Near Field ◽  
Lifetime Measurements ◽  
Spectra Analysis ◽  
Scanning Optical Microscopy ◽  
Doped Polymer ◽  
Near Field Scanning ◽  
The Eu

Eu(DBM)3phen-doped poly(methyl methacryate) (PMMA) with different doping concentration were prepared. The highest doping concentration sample (10000 ppm) was examined by near-field scanning optical microscopy (NSOM) with a resolution of 50 nm; and the result showed that there were no aggregates larger than 50 nm in the doped polymer. This result was further confirmed by optical properties of the doping material. Concentration quenching was not detected by metastable-state lifetime measurements, indicating that no aggregates existed. According to the fluorescence spectra analysis, the relative intensity ratio (R) of 5D0→7F2 to 5D0→7F1 transition was not shown to be significantly changed with the increasing of Eu3+ content. The analysis reflected that the local structure and asymmetry in the vicinity of europium ions were not changed, and that the Eu3+ ions in PMMA were homogeneously dispersed.

Near-field Scanning Optical Microscopy and Electron Microprobe Microscopy Investigations of Immiscibility Effects in Indium Gallium Phosphide Grown by Liquid Phase Epitaxy

2001 ◽  
Vol 667 ◽  
Author(s):  
C. A. Paulson ◽  
A. B. Ellis ◽  
T. F. Kuech
Keyword(s):  
Optical Properties ◽  
Liquid Phase ◽  
Optical Microscopy ◽  
Liquid Phase Epitaxy ◽  
Gallium Phosphide ◽  
Near Field ◽  
Indium Gallium Phosphide ◽  
Indium Gallium ◽  
Scanning Optical Microscopy ◽  
Near Field Scanning

ABSTRACTWe have used Near-field Scanning Optical Microscopy (NSOM) and Electron Probe Microanalysis (EPMA) to study the topographic and microscopic optical properties of indium gallium phosphide (In1−xGaxP) samples grown by Liquid Phase Epitaxy (LPE) on gallium arsenide substrates. Photoluminescence (PL) intensity images gathered using NSOM exhibit strong, highly localized variations in the optical properties of these samples that are seen to occur roughly in registry with the surface topography. Shifts in the PL peak position (by 27 meV) occur across highly mismatched samples with high In content, whereas no shifts were seen for In1−xGaxP films with a nearly lattice matched composition. Compositional fluctuations lead to these PL peak energy shifts, measured by NSOM with a resolution of 250 nm. These composition fluctuations arise from the known solid-solid miscibility gap in the In1−xGaxP system at temperatures used for the growth of these samples.

Fractal clusters in Eu doped polymer fiber studied by near-field scanning optical microscopy

2002 ◽  
Vol 208 (1-3) ◽  
pp. 97-101 ◽  
Author(s):  
Sun Xiaohong ◽  
Ming Hai ◽  
Xie Aifang ◽  
Lu Yonghua ◽  
Xu Xingsheng ◽  
...  
Keyword(s):  
Optical Microscopy ◽  
Near Field ◽  
Polymer Fiber ◽  
Fractal Clusters ◽  
Scanning Optical Microscopy ◽  
Doped Polymer ◽  
Near Field Scanning

Spatiially Resolved Spectra of Miicro-Crystals and Nano-Aggiregates in Doped Polymers

1992 ◽  
Vol 290 ◽  
Author(s):  
Duane Birnbaum ◽  
Seong-Keun Kook ◽  
Raoul Kopelman
Keyword(s):  
Spatial Resolution ◽  
Fluorescence Spectra ◽  
Near Field ◽  
Emission Spectra ◽  
Optical Diffraction ◽  
Near Field Optics ◽  
Spatially Resolved ◽  
Doped Polymers ◽  
Doped Polymer ◽  
Near Field Scanning

AbstractNear-field optics techniques make it possible to by-pass the optical diffraction limit (“uncertainty principle) and attain spatial resolution of λ/50 or better. We present near-field scanning optical spectroscopy (NSOS) data on α and ß mixed micro-crystals of perylene and on various aggregates of tetracene doped into PMMA. The spatial resolution is limited by the size of the scanning photon tip and its distance from the sample. We use nanofabricated optical fiber tips (aluminum coated) that are as small as 100 nm. These can be piezoelectrically scanned close to the sample. Fluorescence spectra easily differentiate between adjoining microcrystallites of α and β perylene, giving spectra identical with those of large (>1 cm) single crystals. The apparently homogeneous molecularly doped polymer samples of tetracene/PMMA have regions that fluoresce anywhere between green and red. Thus the spatially resolved spectra are much sharper and more detailed than the broad and featureless bulk spectra. The different emission spectra are attributed to different aggregates of the tetracene guest embedded in the PMMA host

Near-field scanning optical microscopy

1986 ◽  
Vol 44 ◽  
pp. 642-643
Author(s):  
E. Betzig ◽  
A. Harootunian ◽  
M. Isaacson ◽  
A. Lewis
Keyword(s):  
Near Field ◽  
Optical Microscope ◽  
Visible Radiation ◽  
Field Methods ◽  
Optical Elements ◽  
Optical Region ◽  
Order Of Magnitude ◽  
Nondestructive Imaging ◽  
Scanning Optical Microscopy ◽  
Near Field Scanning

In general, conventional methods of optical imaging are limited in spatial resolution by either the wavelength of the radiation used or by the aberrations of the optical elements. This is true whether one uses a scanning probe or a fixed beam method. The reason for the wavelength limit of resolution is due to the far field methods of producing or detecting the radiation. If one resorts to restricting our probes to the near field optical region, then the possibility exists of obtaining spatial resolutions more than an order of magnitude smaller than the optical wavelength of the radiation used. In this paper, we will describe the principles underlying such "near field" imaging and present some preliminary results from a near field scanning optical microscope (NS0M) that uses visible radiation and is capable of resolutions comparable to an SEM. The advantage of such a technique is the possibility of completely nondestructive imaging in air at spatial resolutions of about 50nm.

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