Structural, magnetic, and dielectric studies on Gd0.7Y0.3MnO3
R M Sarguna1, V Sridharan, S Shanmukharao Samatham
1Condensed Matter Physics Division, Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, India.
Summary
Yttrium substitution in Gadolinium Manganite reveals coupled magnetic and ferroelectric transitions. Specific heat anomalies at 41K and 18K indicate magnetic ordering, while dielectric studies confirm ferroelectricity at 18K.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism and Dielectrics
Background:
- Gadolinium Manganite (GdMnO3) exhibits complex magnetic and multiferroic properties.
- Understanding the interplay between magnetic ordering and ferroelectricity is crucial for novel device applications.
Purpose of the Study:
- To investigate the effects of Yttrium (Y) substitution on the structural, magnetic, and dielectric properties of GdMnO3.
- To elucidate the nature of magnetic transitions and their coupling with ferroelectric ordering.
Main Methods:
- Temperature-dependent structural analysis (lattice parameters).
- Magnetic susceptibility and specific heat measurements.
- Dielectric spectroscopy (frequency-dependent studies).
Main Results:
- Specific heat anomalies at ~41K and 18K, indicating paramagnetic to incommensurate antiferromagnetic (ICAFM) and ICAFM to commensurate antiferromagnetic transitions.
- A ferroelectric transition observed at 18K, confirmed by dielectric anomalies and lattice parameter changes.
- Evidence of strong coupling between Gd3+ and Mn3+ magnetic sublattices, with Y substitution altering relaxation processes.
Conclusions:
- Yttrium substitution in GdMnO3 induces coupled magnetic and ferroelectric transitions.
- Magneto-elastic coupling is present, influencing structural changes across transition temperatures.
- Y substitution significantly modifies the dielectric relaxation behavior, offering pathways for tuning multiferroic properties.
More Related Videos
Related Concept Videos
03:02Colors and Magnetism
12.0K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
12.0K
01:31Magnetic Susceptibility and Permeability
2.9K
In linear magnetic materials, like paramagnets and diamagnets, magnetization is proportional to the magnetic field intensity. The constant of proportionality, a dimensionless number, is called magnetic susceptibility. The value of the susceptibility depends on the type of material.
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...
2.9K
01:26Diamagnetism
2.8K
Materials consisting of paired electrons have zero net magnetic moments. However, when these materials are placed under an external magnetic field, the moments opposite to the field are induced. Such materials are called diamagnets. Diamagnetism is the response of the diamagnets when placed in an external magnetic field.
Diamagnetism was discovered by Anton Brugmans in 1778 when he observed that bismuth gets repelled by magnetic fields, thus theorizing that diamagnets get repelled by magnets....
Diamagnetism was discovered by Anton Brugmans in 1778 when he observed that bismuth gets repelled by magnetic fields, thus theorizing that diamagnets get repelled by magnets....
2.8K
01:31Ferromagnetism
2.8K
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...
2.8K
01:30Paramagnetism
2.4K
Paramagnets are materials with unpaired electrons that possess a finite magnetic moment. In the absence of a magnetic field, these moments are randomly oriented, and thus the net moment is zero. Under an external field, a torque acting on the moments tends to align them along the field's direction. However, the random thermal motion of electrons produces a torque opposite to the external field and tries to disorient the moments. These two competing effects align only a few moments along the...
2.4K