Related Experiment Video
Updated: Nov 3, 2025
15:58
Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing
Published on: December 3, 2013
5.9K
Codoping induced enhanced ferromagnetism in diluted magnetic semiconductors
Antonis N Andriotis1, Madhu Menon2,3
1Institute of Electronic Structure and Laser, FORTH, PO Box 1527, 71110 Heraklio, Crete, Greece.
Summary
Defect-induced magnetism in diluted magnetic semiconductors and transition metal oxides is engineered through doping. This review highlights defect magnetism, exploring its local and holistic effects on magnetic coupling for novel material properties.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism
Background:
- Experimentally observed d0-magnetism is attributed to structural and topological defects.
- Doping and codoping are key methods for engineering magnetic properties in diluted magnetic semiconductors (DMSs) and transition metal oxides (TMOs).
Purpose of the Study:
- To review the fundamental characteristics of defect magnetism across various systems.
- To emphasize the local, holistic, and synergistic responses of host materials to doping.
- To investigate the role of doping in developing magnetic coupling (MC) among magnetic dopants.
Main Methods:
- Review of experimental and theoretical studies on defect-induced magnetism.
- Analysis of ab initio computational results to elucidate local and holistic aspects of MC.
- Comparison with magnetic multilayer systems.
Main Results:
- Defect magnetism is observed in diverse DMSs and TMOs.
- Ab initio calculations reveal charge and spin transfers influencing MC.
- Doping shifts d- and p-band centers, impacting material properties.
Conclusions:
- Magnetic coupling is explained by new successive spin polarization and defect-induced defect-mediated models.
- These models introduce novel contributions to MC, competing with classical mechanisms.
- Similarities between codoped DMSs/TMOs and magnetic multilayers support the proposed models.
More Related Videos
06:53Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
2.2K
09:34Synthesis and Characterization of Fe-doped Aluminosilicate Nanotubes with Enhanced Electron Conductive Properties
Published on: November 15, 2016
9.4K
Related Concept Videos
01:31Ferromagnetism
2.7K
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...
2.7K
01:26Diamagnetism
2.7K
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....
2.7K
01:30Paramagnetism
2.8K
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...
2.8K
03:02Colors and Magnetism
12.7K
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...
12.7K
01:27Biasing of Metal-Semiconductor Junctions
404
Biasing metal-semiconductor junctions involves applying a voltage across the junction. Specifically, the metal is connected to a voltage source, while the semiconductor is grounded. This technique is essential for controlling the direction and magnitude of current flow in electronic devices, including diodes, transistors, and photovoltaic cells.
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
404
01:22Semiconductors
1.0K
There is variation in the electrical conductivity of materials - metals, semiconductors, and insulators that are showcased with the help of the energy band diagrams.
Metals such as copper (Cu), zinc (Zn), or lead (Pb) have low resistivity and feature conduction bands that are either not fully occupied or overlap with the valence band, making a bandgap non-existent. This allows electrons in the highest energy levels of the valence band to easily transition to the conduction band upon gaining...
Metals such as copper (Cu), zinc (Zn), or lead (Pb) have low resistivity and feature conduction bands that are either not fully occupied or overlap with the valence band, making a bandgap non-existent. This allows electrons in the highest energy levels of the valence band to easily transition to the conduction band upon gaining...
1.0K