ELFS spectroscopy (energy loss fine structure) is used to obtain local atomic structure information It can outperform XAFS (x-ray absorption fine structure) not only because of its low Z element sensitivity, but also because of its high spatial resolution and the capability of combining other high resolution TEM measurements. Although TEM continues to gain importance as an indispensable and unique tool to study nanoscale phenomena by providing simultaneous imaging, diffraction, and spectroscopy information, direct observation and quantitative measurements of physical phenomena are also desirable. This paper gives a first-time demonstration of such a measurement, namely local temperature determination in a TEM sample by ELFS.

The principle is simple and as follows. One can measure, with ELFS, the atomic distances up to ±0.01 Å accuracy for the fist shell (typically around 2 Å ) and the second shell (around 3-4 Å). Atomic distances in a sample will change when its temperature changes, the phenomena that are coupled by the macroscopic temperature dependent lattice expansion.