skip to main content

SciTech ConnectSciTech Connect

Title: Phonons and magnetic excitation correlations in weak ferromagnetic YCrO{sub 3}

Here, we report the temperature dependent Raman spectroscopic studies on orthorhombically distorted perovskite YCrO{sub 3} over a temperature range of 20–300 K. Temperature dependence of DC-magnetization measurements under field cooled and zero field cooled protocols confirmed a Néel transition at T{sub N} ∼ 142 K. Magnetization isotherms recorded at 125 K show a clear loop opening without any magnetization saturation up to 20 kOe, indicating a coexistence of antiferromagnetic (AFM) and weak ferromagnetic (WFM) phases. Estimation of exchange constants using mean-field approximation further confirm the presence of a complex magnetic phase below T{sub N}. Temperature evolution of Raman line-shape parameters of the selected modes (associated with the octahedral rotation and A(Y)-shift in the unit-cell) reveal an anomalous phonon shift near T{sub N}. An additional phonon anomaly was identified at T{sup *} ∼ 60 K, which could possibly be attributed to the change in the spin dynamics. Moreover, the positive and negative shifts in Raman frequencies between T{sub N} and T{sup *} suggest competing WFM and AFM interactions. A close match between the phonon frequency of B{sub 3g} (3)-octahedral rotation mode with the square of sublattice magnetization between T{sub N} and T{sup *} is indicative of the presence of spin-phonon coupling in multiferroic YCrO{sub 3}.
Authors:
; ; ;  [1] ;  [2] ;  [2] ;  [3] ;  [4] ;  [5]
  1. Department of Physics, University of Puerto Rico, Puerto Rico 00936-8377 (United States)
  2. Department of Physics, Indian Institute of Technology, Kanpur (India)
  3. (India)
  4. Department of Materials Science and Engineering, Indian Institute of Technology, Kanpur (India)
  5. Department of Physics, Indian Institute of Technology, Delhi (India)
Publication Date:
OSTI Identifier:
22275553
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 18; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANTIFERROMAGNETISM; APPROXIMATIONS; ATOMIC FORCE MICROSCOPY; CHROMATES; CORRELATIONS; ELECTRON-PHONON COUPLING; EXCITATION; FERROMAGNETISM; ISOTHERMS; MAGNETIZATION; MEAN-FIELD THEORY; PHONONS; RAMAN SPECTROSCOPY; ROTATION; TEMPERATURE DEPENDENCE; YTTRIUM COMPOUNDS