Apparatus for processing of samples at high pressures and high temperatures in a fast quenching-rate regime and synthesis of polyacetylene by pulsed laser heating of confined carbon thin films

It is widely accepted that the lower mantle consists of mainly three major minerals—ferropericlase, bridgmanite and calcium silicate perovskite. Ferropericlase ((Mg,Fe)O) is the second most abundant of the three, comprising approximately 16–20 wt% of the lower mantle. The stability of ferropericlase at conditions of the lowermost mantle has been highly investigated, with controversial results. Amongst other reasons, the experimental conditions during laser heating (such as duration and achieved temperature) have been suggested as a possible explanation for the discrepancy. In this study, we investigate the effect of pulsed laser heating on the stability of ferropericlase, with a geochemically relevant composition of Mg0.76Fe0.24O (Fp24) at pressure conditions corresponding to the upper part of the lower mantle and at a wide temperature range. We report on the decomposition of Fp24 with the formation of a high-pressure (Mg,Fe)3O4 phase with CaTi2O4-type structure, as well as the dissociation of Fp24 into Fe-rich and Mg-rich phases induced by pulsed laser heating. Our results provide further arguments that the chemical composition of the lower mantle is more complex than initially thought, and that the compositional inhomogeneity is not only a characteristic of the lowermost part, but includes depths as shallow as below the transition zone.

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Thermal Shock and Thermal Fatigue of Ferroelectric Thin Film due to Pulsed Laser Heating

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.9.69 ◽

2005 ◽

Vol 9 ◽

pp. 69-78 ◽

Cited By ~ 3

Author(s):

X.J. Zheng ◽

S.F. Deng ◽

Yi Chun Zhou ◽

Naotake Noda

Keyword(s):

Thin Film ◽

Thin Films ◽

Thermal Shock ◽

Thermal Fatigue ◽

Laser Heating ◽

Ferroelectric Properties ◽

Pulsed Laser ◽

Pzt Thin Film ◽

Heating Test ◽

Pulsed Laser Heating

Thermal shock and thermal fatigue of ferroelectric (FE) thin films were investigated by the pulsed laser tests. The power density was gradually increasing in the single pulsed laser heating test which simulated a thermal shock, the part melting threshold of Pb(Zr0.52Ti0.48)O3 (PZT) thin films was found by scanning electron microscopy (SEM). After thermal shock resulted the highest temperature below Curie point at the surface of PZT thin film, X-ray diffraction (XRD), SEM and RT66A standard ferroelectrics analyzer were used to study the microstructure, crystal grain sizes, and ferroelectric failure behavior. It was found that XRD peak of PZT thin film after laser beam heating was stronger than that before laser beam heating, crystal grain sizes decreased, and the ferroelectric properties were degraded. However there was no crack observed by SEM, until PZT thin films were melted. The fined grain effects on ferroelectric properties and XRD patterns of PZT thin film, depolarization due to the single pulsed laser heating were discussed respectively. The pulsed cycles with a certain power density were gradually increasing in the repetition pulsed laser heating test. It was interesting to find that the cracks will initiate and propagate due to the thermal fatigue induced by the repetition pulsed laser. The possible origins of the thermal fatigue cracks were also discussed.

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Pulsed laser deposition and characterization of multilayer metal-carbon thin films

Applied Surface Science ◽

10.1016/j.apsusc.2011.02.032 ◽

2011 ◽

Vol 257 (15) ◽

pp. 6445-6450 ◽

Cited By ~ 13

Author(s):

K. Siraj ◽

M. Khaleeq-ur-Rahman ◽

M.S. Rafique ◽

M.Z. Munawar ◽

S. Naseem ◽

...

Keyword(s):

Thin Films ◽

Pulsed Laser Deposition ◽

Pulsed Laser ◽

Laser Deposition ◽

Carbon Thin Films ◽

Multilayer Metal

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Pulsed laser heating of soot: morphological changes

Carbon ◽

10.1016/s0008-6223(98)00169-9 ◽

1999 ◽

Vol 37 (2) ◽

pp. 231-239 ◽

Cited By ~ 80

Author(s):

Randy L Vander Wal ◽

Mun Y Choi

Keyword(s):

Laser Heating ◽

Morphological Changes ◽

Pulsed Laser ◽

Pulsed Laser Heating

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In-Situ Diagnostics at High Pressures: Ellipsometric and Rheed Studies of the Growth of Yba2Cu3O7

MRS Proceedings ◽

10.1557/proc-502-237 ◽

1997 ◽

Vol 502 ◽

Cited By ~ 4

Author(s):

Dave H. A. Blank ◽

Horst Rogalla

Keyword(s):

Thin Films ◽

High Pressures ◽

High Vacuum ◽

Pulsed Laser ◽

Complex Oxide ◽

High Energy ◽

Diagnostic Tools ◽

Heteroepitaxial Growth ◽

Deposition Parameters

ABSTRACTPulsed Laser and Sputter Deposition are used for the fabrication of complex oxide thin films at relatively high oxygen pressures (up to 0.5 mBar). This high pressure hampers the application of a number of in-situ diagnostic tools. One of the exceptions is ellipsometry. Using this technique we studied in-situ the growth of off-axis sputtered Yba2Cu3O6+x thin films on (001) SrTiO3 as a function of the deposition parameters. Furthermore, the oxidation process from O(6) to O(7) has been studied by performing spectroscopic ellipsometry during isobaric cooling procedures.Another suitable in-situ monitoring technique for the growth of thin films is Reflection High Energy Electron Diffraction (RHEED). In general this is a (high) vacuum technique. Here, we present an RHEED-system in which we can observe clear diffraction patterns up to a deposition pressure of 0.5 mBar. The system has been used for in-situ monitoring of the heteroepitaxial growth of YBa2Cu3 06+x on SrTiO3 by pulsed laser deposition.

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Thermal Modeling of the Cavity in Pulsed Excimer Laser Calorimeters

10.1115/imece2000-1574 ◽

2000 ◽

Author(s):

D. H. Chen ◽

Z. M. Zhang

Keyword(s):

Laser Heating ◽

Average Power ◽

Pulsed Laser ◽

Thermal Response ◽

Element Model ◽

Electrical Heating ◽

Deep Ultraviolet ◽

Simplified Finite Element Model ◽

193 Nm ◽

Pulsed Laser Heating

Abstract A simplified finite element model is built to study the thermal response of the 193-nm pulsed-laser calorimeter. The nonequivalence between pulsed-laser heating and electrical heating is estimated to be 0.46% at the thermocouple locations by comparing the calibration factors for average-power laser heating and electrical heating. This study should help the development of calibration and measurement standards in pulsed energy measurements for deep ultraviolet excimer lasers that are important for photolithographic and materials processing applications.

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