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Updated: Nov 28, 2025
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Quantitative Atomic-Site Analysis of Functional Dopants/Point Defects in Crystalline Materials by Electron-Channeling-Enhanced Microanalysis
Published on: May 10, 2021
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Electron-phonon coupling in APd3O4: A = Ca, Sr, and Sr0.85Li0.15
Bommareddy Poojitha1, B H Reddy1, Aprajita Joshi1
1Department of Physics, Indian Institute of Science Education and Research, Bhopal 462066, India.
Summary
Electron phonon coupling influences the Raman spectrum of APd3O4 semiconductors and Sr0.85Li0.15Pd3O4. Enhanced coupling in the doped compound at low temperatures is linked to its metallicity.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spectroscopy
Background:
- Narrow bandgap semiconductors APd3O4 (A = Ca, Sr) and hole-doped Sr0.85Li0.15Pd3O4 are investigated.
- Raman spectroscopy is a key technique for probing vibrational and electronic properties.
Purpose of the Study:
- To investigate the role of electron phonon coupling in the Raman spectrum of APd3O4 and Sr0.85Li0.15Pd3O4.
- To understand the origin of electronic continuum states and their interaction with phonons.
Main Methods:
- Raman spectroscopy measurements at room temperature.
- Laser power-dependent and temperature-dependent Raman spectroscopy.
- Factor group analysis to predict Raman active phonons.
Main Results:
- Four Raman active phonons were observed in all three compounds.
- A Fano-like lineshape for the lowest energy phonon (Pd vibrations) indicates electron-phonon coupling.
- Enhanced electron-phonon coupling strength was observed in Sr0.85Li0.15Pd3O4 at low temperatures.
Conclusions:
- Electron phonon coupling significantly impacts the Raman spectrum of these materials.
- The observed Fano-like lineshape confirms the interaction between phonons and electronic continuum states.
- The enhanced electron-phonon coupling in the doped compound is attributed to its metallicity.
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