Formation and assignment of silver defect centres in phosphate glass induced by femtosecond laser pulses

Nuclear Instruments and Methods in Physics Research Section B:

2011

The direct observation and characterisation of silver nanoparticles or clusters embedded in a Ag + -activated phosphate glass (PG:Ag) was demonstrated. Correlations between the isolated Ag + concentration and X-ray-induced silver species were systematically examined using optical measurements. Evidence of spherical silver nanoparticles or clusters in X-ray-irradiated PG:Ag with sizes ranging from 5 to 30 nm was obtained from the lattice spacings and from energy dispersive X-ray spectroscopy (EDXS) combined with transmission electron microscopy (TEM). Three-dimensional (3D) contour plots using combined excitation-emission spectroscopy (CEES) were also recorded for X-ray-irradiated PG:Ag to allow identification of the complicated spectroscopic features of the sample.

Section: Introductionmentioning

confidence: 99%

Observation and partly characterisation of silver nanoparticles in X-ray irradiated radiophotoluminescent phosphate glass

Zheng

Nuclear Instruments and Methods in Physics Research Section B:

2011

“…Such a behaviour, i.e., the ratios of the orange to blue RPL intensity in Ag-activated phosphate glass, was strongly sensitive to the radiation types, such as alpha 15) and gamma rays 7) ; to the pulse duration, such as a femtosecond laser; 16) and to the irradiation conditions at different temperatures and excitation photon energy. 17) A set of the time-resolved RPL spectra over 80 curves at different depths, with a step As the similar spectra of Fig. 3, a set of the time-resolved RPL spectra over 80 curves at different depths under X-ray irradiation were also measured, as shown in Fig.…”

Section: Resultsmentioning

confidence: 99%

A three-dimensional imaging detector based on nano-scale silver-related defects in X- and gamma-ray-irradiated glasses

Yanagida²,

Chen³

2015

Jpn. J. Appl. Phys.

Ag-activated phosphate glass, which is the most commonly known radiophotoluminescent (RPL) material, has the capability to operate not only dosimeters but also two-and three-dimensional (2D and 3D) dose imaging detectors in the same host. This passive detector is based on radiation-induced, optically active nano-scale defects. In this work, the transient-state optical properties of the blue and orange RPL were investigated using a time-resolved spectrum technique for 137 Cs and 60 Co gamma-ray-irradiated Ag-activated phosphate glass. Specifically, the blue RPL intensity with a decay time of 5 ns as a function of the depth at the vicinity of the surface was systematically examined to clarify an accurate dose distribution within the glass. Moreover, a feasibility study into the use of an RPL Ag-activated phosphate glass detector for fluorescent nuclear track imaging was demonstrated using a confocal fluorescence image microscope for the first time.

“…In addition, the origin, formation kinetics and optical properties were also investigated with a peak-fitting analysis, a high-repetition-rate femtosecond (fs) laser technique, an RPL decay curve analysis, a heat treatment, and transmission electron microscopy (TEM) (Zheng and Kurobori, 2011a;Zheng et al, 2011;Zheng and Kurobori, 2011b).…”

Section: Resultsmentioning

confidence: 99%

A novel disk-type X-ray area imaging detector using radiophotoluminescence in silver-activated phosphate glass

Nakamura

2012

Radiation Measurements

We report a novel two-and three-dimensional (2-D, 3-D) imaging detector based on the radiophotoluminescence (RPL) phenomenon in silver-activated phosphate glass (PG:Ag) and evaluate its dosimetric characteristics. A compact disk-type PG:Ag detector with a diameter of 80 mm was rotated at a rate of 400 rpm to read out the accumulated dose information and then remove the images for reuse. After X-ray exposure, three RPL dosimeter processes, i.e., preheating, reading, and erasing, were carried out with only a UV laser at 375 nm by adjusting the stepwise output levels. The 3-D images and dose distributions were rapidly reconstructed with a high spatial resolution of 1 μm and a sensitivity of 1 mGy.