Emergent excitation in the paramagnetic phase of geometrically frustrated GdMn2O5

Lattice Dynamics of Gd1−xYxMn2O5 Investigated by Infrared Spectroscopy

“…In the family of Mn 2 O 5 , GdMn 2 O 5 is a unique multiferroic with largest polarization under strong magnetic field among the known multiferroics [3]. Very recently, we have observed a magnetodielectric effect in the paramagnetic phase of GdMn 2 O 5 [10] as well as in DyMn 2 O 5 [11]. This unusual magnetodielectric behavior in GdMn 2 O 5 is consistent with the softening of Raman active phonons, indicating a distinct magnetic correlation slightly above [12].…”

“…Gd 1− Y Mn 2 O 5 ceramic samples have been synthesized by using sol-gel method, similar to other Mn 2 O 5 compounds [10,11,21]. Fourier transform infrared (FTIR) spectrometer (Vertex 80v) has been used to measure the IR reflectivity.…”

“…Moreover, the softening of infrared active modes has also been observed in DyMn 2 O 5 above [13]. In case of GdMn 2 O 5 , magnetoelectric effect and spin-lattice coupling are commonly acknowledged in several investigations [4,10,12,14]; little is known about the correlations between structural distortion and lattice dynamics. Infrared spectroscopy demonstrates the local lattice distortion and provides the information about the flexible crystalline lattice.…”

Lattice Dynamics and Transport Properties of Multiferroic DyMn2O5

“…Remarkably, recently we have observed an unconventional magnetodielectric effect in DyMn 2 O 5 above , where the infrared and Raman phonons have shown spin-phonon coupling and confirm the strong correlation between spin, charge, and lattice degree of freedom [8]. Such a strong interplay between many degrees of freedom in the paramagnetic phase is a special characteristic of Mn 2 O 5 family [5][6][7][8][9]. The knowledge of lattice vibrations and their correlation to different conduction mechanisms is of crucial importance for engineering the materials for various technological applications.…”

“…The sample was synthesized by using the sol-gel technique as described previously [9]. Stoichiometric amounts of Gd and Mn nitrates were dissolved into distilled water and stirred for 2 h along with heating at 80 ∘ C until viscous gel was formed.…”