Emergence of spin-phonon coupling in Gd-doped Y$_2$CoMnO$_6$ double perovskite oxide: a combined experimental and ab-initio study
| Autor: | Khan, Anasua, Banerjee, Debdatta, Rawat, Divya, Nath, T. K, Soni, Ajay, Chatterjee, Swastika, Taraphder, A. |
|---|---|
| Rok vydání: | 2024 |
| Předmět: | |
| Druh dokumentu: | Working Paper |
| Popis: | One of the fundamental interactions that is found in many functional materials is the spin-phonon coupling (SPC), which is at the heart of many novel functionalities. The simultaneous presence of multi-magnetic phases makes SPC even more intriguing. We have used Raman spectroscopy as well as first-principles methods to investigate the possibility of the appearance of SPC in Gd-doped Y$_2$CoMnO$_6$ (YGCMO) double perovskite oxide and the influence of anti-site disorder on the same. YGCMO is found to exhibit anti-site disorder leading to both ferromagnetic (between Co and Mn) and anti-ferromagnetic interactions (Co-Co, Mn-Mn, Gd-Co/Mn). An analysis of the temperature-dependent phonon frequency for the stretching modes of YGCMO, obtained using RAMAN spectroscopy, indicates that SPC is possibly emerging from simultaneous presence of ferromagnetic and antiferromagnetic interactions. The nature of the phonon linewidth and the insulating state of the material eliminate the role of magnetostriction on the observed anomaly. The spin-phonon coupling strength comes out to be 0.29 cm$^{-1}$. Our experimental findings are corroborated by first-principles DFT calculations which indicate the presence of SPC in ordered YGCMO getting enhanced in the presence of anti-site disorder. This indicates a strong influence of B-site (Co/Mn) ordering on SPC in the bulk double perovskite systems. An analysis of the cause behind the enhanced SPC in the presence of anti-site disorder is also presented. Comment: 23 pages, 14 figures |
| Databáze: | arXiv |
| Externí odkaz: |
|