Variation of Phonons Self-energy - Frequency and Linewidth - of Permanent Phonons in YBCO/LCMO Superlattices Thin Films Due to the Change of Temperature Using Raman Light Scattering

In order to write this article, we looked at the impact of temperatures variation going from low to high temperature starting from 10 K to 300 K on my samples. The work was performed by using Raman light scattering which is a powerful technique to fulfill that aim perfectly on thin films of YBCO/LCMO superlatticse - with different thickness of both YBCO layers and LCMO layers -, bulk YBCO and bulk LCMO as seen in table 1. During this work, we focus our study on the permanent phonons of YBCO/LCMO as a thin film, which were 240 cm⁻¹, 340 cm⁻¹, 440 cm⁻¹ and 505 cm⁻¹ phonon modes. Depending on our data, which we obtained from experiment’s measurement we could confirm that the variation of temperature gives rise to change in frequency and linewidth in all phonons were observed during this study. Therefore, we could conclude that the all phonons studied in this article collapse depending on the increasing of the temperature in the form of suppression of phonons self-energy in the form of softening and hardening, but with different degrees. Because of that, we clearly observed expected and unexpected behaviour of frequency and linewidth of all permanent phonons of YBCO/LCMO thin films - where we partially builded up our work on this observation in this article - at TC and TCurie, respectively.