Magnetic properties and their correlation with lattice dynamics in HoFe1-xCrxO3 (0 ≤ x ≤ 1) compounds

Perovskites with general formula ABO3 (A is rare earth ion or Yttrium and B is a transition metal) have been the most versatile compounds in oxide research. Among various perovskite oxides, rare earth orthoferrite (RFeO3) and orthochromite (RCrO3) compounds with distorted perovskite structure have drawn considerable attention due to their unique physical properties and potential applications. Among RFeO3 compounds, holmium orthoferrite (HoFeO3) has been studied extensively for ultrafast recording applications. The crystal structure of HoFeO3 is orthorhombic with a space group of Pbnm at room temperature and possesses G-type antiferromagnetic with a magnetic ordering temperature (TN) around 641 K. Apart from TN, HoFeO3 exhibits the spin reorientation (SR) transition of Fe3+ at 50 - 60 K. According to Goodenough-Kanamori theory, Cr3+ is best choice for Fe3+ to show superior magnetic properties due to super exchange interactions, which may exhibit interesting magnetic properties and lattice dynamics. Hence, in this thesis we explored the structural, magnetic properties and their correlation with lattice dynamics in HoFe1- xCr xO 3 (0 ≤ x ≤ 1) compounds

A comprehensive review on the ferroelectric orthochromates: Synthesis, property, and application

Multiferroics represent a class of advanced materials for promising applications and stand at the forefront of modern science for the special feature possessing both charge polar and magnetic order. Previous studies indicate that the family of RECrO3 (RE = rare earth) compounds is likely another rare candidate system holding both ferroelectricity and magnetism. However, many issues remain unsolved, casting hot disputes about whether RECrO3 is multiferroic or not. For example, an incompatibility exists between reported structural models and observed ferroelectric behaviors, and it is not easy to determine the spin canting degree. To address these questions, one key step is to grow single crystals because they can provide more reliable information than other forms of matter do. In this review, the parent and doped ferroelectric YCrO3 compounds are comprehensively reviewed based on scientific and patent literatures from 1954 to 2022. The materials syntheses with different methods, including poly-, nano-, and single-crystalline samples and thin films, are summarized. The structural, magnetic, ferroelectric and dielectric, optical, and chemical-pressure (on Y and Cr sites by doping) dependent chemical and physical properties and the corresponding phase diagrams, are discussed. Diverse (potential) applications, including anti-corrosion, magnetohydrodynamic electrode, catalyst, negative-temperature-coefficient thermistor, magnetic refrigeration, protective coating, and solid oxide fuel cell, are present. To conclude, we summarize general results, reached consensuses, and existing controversies of the past nearly 69 years of intensive studies and highlight future research opportunities and emerging challenges to address existing issues.Comment: 69 pages, 35 figures, accepted by Coordination Chemistry Review

The propagation circuits for magnetic bubble-domain devices

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