New experimental results of an international collaboration, led by BME associate professor Sándor Bordács, has been published in Physical Review Letters.
The team, consisting of Japanese, Estonian and Hungarian researchers, have observed an unusual form of spin-lattice coupling using infrared spectroscopy. In multiferroic Swedenborgites, the lifetime of lattice vibrations (phonons) is strongly suppressed, and the phonons are scattered by the magnetic fluctuations of the disordered paramagnetic phase. According to the explanation of the authors, the orbital degrees of freedom of the transition metal electrons play a key role in the enhanced spin-lattice interaction. The results have been published in Physical Review Letters.
Vilmos Kocsis, Yusuke Tokunaga, Toomas Rõõm, Urmas Nagel, Jun Fujioka, Yasujiro Taguchi, Yoshinori Tokura, and Sándor Bordács
Spin-Lattice and Magnetoelectric Couplings Enhanced by Orbital Degrees of Freedom in Polar Multiferroic Semiconductors