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  • Exploring Photothermal Pathways via in Situ Laser Heating in the Transmission Electron Microscope: Recrystallization, Grain Growth, Phase Separation, and Dewetting in Ag 0.5 Ni 0.5 Thin Films
Title: Exploring Photothermal Pathways via in Situ Laser Heating in the Transmission Electron Microscope: Recrystallization, Grain Growth, Phase Separation, and Dewetting in Ag 0.5 Ni 0.5 Thin Films
Abstract A new optical delivery system has been developed for the (scanning) transmission electron microscope. Here we describe the in situ and “rapid ex situ ” photothermal heating modality of the system, which delivers >200 mW of optical power from a fiber-coupled laser diode to a 3.7 μ m radius spot on the sample. Selected thermal pathways can be accessed via judicious choices of the laser power, pulse width, number of pulses, and radial position. The long optical working distance mitigates any charging artifacts and tremendous thermal stability is observed in both pulsed and continuous wave conditions, notably, no drift correction is applied in any experiment. To demonstrate the optical delivery system’s capability, we explore the recrystallization, grain growth, phase separation, and solid state dewetting of a Ag 0.5 Ni 0.5 film. Finally, we demonstrate that the structural and chemical aspects of the resulting dewetted films was assessed.  more » « less
Award ID(s):
1746019 1709275 1603780 1709601
PAR ID:
10084719
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Microscopy and Microanalysis
Volume:
24
Issue:
6
ISSN:
1431-9276
Page Range / eLocation ID:
647 to 656
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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