Stabilizing electromagnons in CuO under pressure

• Published in: npj quantum materials Vol. 8; no. 1; pp. 11 - 7
• Main Authors: Verseils, M., Hemme, P., Bounoua, D., Cervasio, R., Brubach, J-B., Houver, S., Gallais, Y., Sacuto, A., Colson, D., Iijima, T., Mochizuki, M., Roy, P., Cazayous, M.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 24.02.2023; Nature Publishing Group; Nature publishing; Nature Portfolio
• Subjects: 639/301; 639/301/119/996; Condensed Matter; Condensed Matter Physics; Copper oxides; Electric fields; Energy; Heisenberg theory; Hydrostatic pressure; Infrared radiation; Low pressure; Low temperature; Magnons; Phase diagrams; Physics; Physics and Astronomy; Quantum Physics; Radiation; Single crystals; Spectrum analysis; Spin dynamics; Statistical models; Structural Materials; Surfaces and Interfaces; Synchrotron radiation; Synchrotrons; Temperature; Thin Films
• ISSN: 2397-4648; 2397-4648
• DOI: 10.1038/s41535-023-00542-1

Electromagnons (Electroactive spin wave excitations) could prove to be decisive in information technologies but they remain fragile quantum objects, mainly existing at low temperatures. Any future technological application requires overcoming these two limitations. By means of synchrotron radiation infrared spectroscopy performed in the THz energy range and under hydrostatic pressure, we tracked the electromagnon in the cupric oxide CuO, despite its very low absorption intensity. We demonstrate how a low pressure of 3.3 GPa strongly increases the strength of the electromagnon and expands its existence to a large temperature range enhanced by 40 K. Accordingly, these two combined effects make the electromagnon of CuO under pressure a more ductile quantum object. Numerical simulations based on an extended Heisenberg model were combined to the Monte-Carlo technique and spin dynamics to account for the magnetic phase diagram of CuO. They enable to simulate the absorbance response of the CuO electromagnons in the THz range.