Observation, Evidence and Origin of Room Temperature Magnetodielectric Effect in Mn doped LaGaO3

TL;DR

This study reports a room temperature magnetodielectric effect in Mn doped LaGaO3, attributed to spin-phonon coupling and magnetostriction, with potential for magnetodielectric applications.

Contribution

First observation of RTMD effect in Mn doped LaGaO3 validated by Raman spectroscopy and magnetoresistance measurements, highlighting intrinsic spin-phonon coupling mechanisms.

Findings

RTMD effect observed at room temperature.

Magnetoresistance measurements exclude magnetoresistive contribution.

Magnetic field induces Raman mode hardening indicating spin-phonon coupling.

Abstract

We report an observation of room temperature magnetodielectric (RTMD) effect in Mn doped LaGaO3. Results of frequency dependent magnetoresistance (FDMR) measurements discards the possibility of any magnetoresistive contribution in the observed MD effect. The intrinsic nature of MD coupling has been validated/evidenced by means of magnetic field dependent Raman spectroscopy and explained in terms of modified volume strain governed by magnetic field induced rerotation of spin coupled Mn-orbitals. Ultimately, present RTMD effect is attributed to magneto-compression/magnetostriction associated with spin-phonon coupling as evidenced in the form of magnetic field induced hardening of symmetric stretching (SS) MnO6 octahedral Raman modes. Presently studied Mn doped LaGaO3 can be a candidate for magnetodielectric applications.