Strain control of Urbach energy in Cr-doped PrFeO3


Polycrystalline samples of PrFe1−x CrxO3 having average particle size of ~90 nm have been prepared by wet chemical route. The structural phase purity of the prepared samples is confirmed by powder X-ray diffraction followed by Rietveld refinements. It is observed that with Cr doping, the Urbach energy (E u) increases. The E u is measure of the various disorders present in the sample, such as chemical and structural. To understand the contribution to the E u due to chemical and structural disorders, we have probed the chemical and structural disorders in the samples by elemental mappings and through X-ray diffraction experiments, respectively. Elemental mapping confirms chemical homogeneity of prepared samples. It is observed that with Cr doping the crystallographic strain increases and Urbach energy shows the similar scaling.

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All authors sincerely thank SIC IIT Indore for providing characterization facilities. CSIR, New Delhi is acknowledged for funding high temperature furnace under the project 03(1274)/13/EMR-II used for the sample preparations. The authors VM and KW acknowledge the Ministry of Human Resource Development (MHRD), government of India for providing financial support as Teaching Assistantship. Dr. Archna Sagdeo, scientific officer, RRCAT Indore is acknowledged for extending the X-ray diffraction facilities.

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Correspondence to Pankaj R. Sagdeo.

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Kumar, A., Warshi, M.K., Mishra, V. et al. Strain control of Urbach energy in Cr-doped PrFeO3 . Appl. Phys. A 123, 576 (2017).

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