posted on 2024-01-30, 14:39authored byWon-Woo Park, Pavel K. Olshin, Ye-Jin Kim, Hak-Won Nho, Daria V. Mamonova, Ilya E. Kolesnikov, Vassily A. Medvedev, Oh-Hoon Kwon
When navigated by the available energy
of a system, often
provided
in the form of heat, physical processes or chemical reactions fleet
on a free-energy landscape, thus changing the structure. In in situ transmission electron microscopy (TEM), where material
structures are measured and manipulated inside the microscope while
being subjected to external stimuli such as electrical fields, laser
irradiation, or mechanical stress, it is necessary to precisely determine
the local temperature of the specimen to provide a comprehensive understanding
of material behavior and to establish the relationship among energy,
structure, and properties at the nanoscale. Here, we propose using
cathodoluminescence (CL) spectroscopy in TEM for in situ measurement of the local temperature. Gadolinium oxide particles
doped with emissive europium ions present an opportunity to utilize
them as a temperature probe in CL measurements via a ratiometric approach.
We show the thermometric performance of the probe and demonstrate
a precision of ±5 K in the temperature range from 113 to 323
K with the spatial resolution limited by the size of the particles,
which surpasses other methods for temperature determination. With
the CL-based thermometry, we further demonstrate measuring local temperature
under laser irradiation.