Time-resolved mechanoluminescence of optical materials

The fluorescence spectra of four optical materials (S1-UV quartz, UV grade sapphire, MgF2, and BaF2) have been recorded using ArF laser radiation at 193 nm (6.4 eV) as an excitation source. The time-resolved fluorescence intensities have also been measured at several wavelengths using a transient digitizer with 2 ns resolution. All of the materials exhibit a fast fluorescence which follows the exciting laser pulse and has a lifetime τR < 7 ± 2 ns. This fast fluorescence is present as a broad continum from 200 to 1000 nm with maxima in the UV and the IR. In addition, there are fluorescence components with longer lifetimes which are characteristic of the individual materials. The results suggest further opportunities for study of optical materials using ArF lasers and indicate an area of caution to be exercised by experimentalists employing ArF lasers for excitation experiments.

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Time-resolved phase microscopy for the study of laser-material interactions in optical materials

2016 Progress in Electromagnetic Research Symposium (PIERS) ◽

10.1109/piers.2016.7735003 ◽

2016 ◽

Author(s):

L. Gallais ◽

S. Monneret

Keyword(s):

Optical Materials ◽

Time Resolved ◽

Laser Material ◽

Phase Microscopy

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The Applications of Terahertz Spectroscopy in Functional Optical Materials Researches

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.320.133 ◽

2013 ◽

Vol 320 ◽

pp. 133-137

Author(s):

Xiao Jian Fu ◽

Ji Zhou

Keyword(s):

Optical Materials ◽

Yttrium Aluminum Garnet ◽

Terahertz Spectroscopy ◽

Functional Materials ◽

Thz Spectroscopy ◽

Thz Radiation ◽

Terahertz Time Domain Spectroscopy ◽

Time Resolved ◽

Injection Process ◽

Security Inspection

Terahertz radiation refers to the electromagnetic wave whose frequency is usually defined between 0.1 and 10 THz (1 THz=1012 Hz). With the development of the emission and detection technologies of THz radiation, terahertz time-domain spectroscopy (THz-TDS) has been widely used in medical diagnosis, security inspection and materials characterization. In this paper, we introduced briefly the progress of terahertz measurement technologies, and then reviewed the applications of THz spectra in functional materials researches. As two important functional optical materials, TiO2 nanoparticles and yttrium aluminum garnet (YAG) crystal have been investigated with THz-TDS. We introduced the electron injection process in TiO2 studied by time resolved THz spectroscopy which is reported in the literature, and then presented our own work, the THz optical constants of undoped and Tm3+ doped YAG crystals.

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Time-resolved Fourier spectroscopy for activated optical materials

Applied Optics ◽

10.1364/ao.35.002849 ◽

1996 ◽

Vol 35 (16) ◽

pp. 2849 ◽

Cited By ~ 9

Author(s):

H. Weidner ◽

R. E. Peale

Keyword(s):

Optical Materials ◽

Fourier Spectroscopy ◽

Time Resolved

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Microtubule nucleation sequence studied by time-resolved x-ray scattering and electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100077402 ◽

1983 ◽

Vol 41 ◽

pp. 766-767

Author(s):

Eva-Maria Mandelkow ◽

Eckhard Mandelkow ◽

Joan Bordas

Keyword(s):

Electron Microscopy ◽

Dynamic Equilibrium ◽

Time Resolved ◽

X Ray ◽

Additional Information ◽

X Ray Scattering ◽

Low Concentrations ◽

Microtubule Growth ◽

Ray Patterns ◽

Ray Scattering

When a solution of microtubule protein is changed from non-polymerising to polymerising conditions (e.g. by temperature jump or mixing with GTP) there is a series of structural transitions preceding microtubule growth. These have been detected by time-resolved X-ray scattering using synchrotron radiation, and they may be classified into pre-nucleation and nucleation events. X-ray patterns are good indicators for the average behavior of the particles in solution, but they are difficult to interpret unless additional information on their structure is available. We therefore studied the assembly process by electron microscopy under conditions approaching those of the X-ray experiment. There are two difficulties in the EM approach: One is that the particles important for assembly are usually small and not very regular and therefore tend to be overlooked. Secondly EM specimens require low concentrations which favor disassembly of the particles one wants to observe since there is a dynamic equilibrium between polymers and subunits.

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Electron Channeling Patterns

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100077700 ◽

1977 ◽

Vol 35 ◽

pp. 12-13

Author(s):

David C. Joy

Keyword(s):

Electron Diffraction ◽

Incidence Angle ◽

Photographic Plate ◽

Diffraction Effect ◽

Angle Of Incidence ◽

Bulk Single Crystal ◽

Time Resolved ◽

Electron Channeling ◽

Spatially Resolved ◽

Large Bulk

Electron channeling patterns (ECP) were first found by Coates (1967) while observing a large bulk, single crystal of silicon in a scanning electron microscope. The geometric pattern visible was shown to be produced as a result of the changes in the angle of incidence, between the beam and the specimen surface normal, which occur when the sample is examined at low magnification (Booker, Shaw, Whelan and Hirsch 1967).A conventional electron diffraction pattern consists of an angularly resolved intensity distribution in space which may be directly viewed on a fluorescent screen or recorded on a photographic plate. An ECP, on the other hand, is produced as the result of changes in the signal collected by a suitable electron detector as the incidence angle is varied. If an integrating detector is used, or if the beam traverses the surface at a fixed angle, then no channeling contrast will be observed. The ECP is thus a time resolved electron diffraction effect. It can therefore be related to spatially resolved diffraction phenomena by an application of the concepts of reciprocity (Cowley 1969).

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Time-resolved high-resolution electron microscopy of structural stability in mgo clusters

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100165823 ◽

1996 ◽

Vol 54 ◽

pp. 672-673

Author(s):

T. Kizuka ◽

N. Tanaka

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Magnesium Oxide ◽

Structural Stability ◽

High Resolution Electron Microscopy ◽

Video Tape ◽

Solid State Physics ◽

Time Resolved ◽

Resolution Electron ◽

Structural And Functional Properties

Structure and stability of atomic clusters have been studied by time-resolved high-resolution electron microscopy (TRHREM). Typical examples are observations of structural fluctuation in gold (Au) clusters supported on silicon oxide films, graphtized carbon films and magnesium oxide (MgO) films. All the observations have been performed on the clusters consisted of single metal element. Structural stability of ceramics clusters, such as metal-oxide, metal-nitride and metal-carbide clusters, has not been observed by TRHREM although the clusters show anomalous structural and functional properties concerning to solid state physics and materials science.In the present study, the behavior of ceramic, magnesium oxide (MgO) clusters is for the first time observed by TRHREM at 1/60 s time resolution and at atomic resolution down to 0.2 nm.MgO and gold were subsequently deposited on sodium chloride (001) substrates. The specimens, single crystalline MgO films on which Au particles were dispersed were separated in distilled water and observed by using a 200-kV high-resolution electron microscope (JEOL, JEM2010) equipped with a high sensitive TV camera and a video tape recorder system.

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