Author: Xiaomei Feng-Brames
Publisher:
ISBN:
Category :
Languages : de
Pages : 125
Book Description
Magneto-transport and magneto-optical properties of δ-doped [delta-doped] InP near the metal insulator transition
Author: Xiaomei Feng-Brames
Publisher:
ISBN:
Category :
Languages : de
Pages : 125
Book Description
Publisher:
ISBN:
Category :
Languages : de
Pages : 125
Book Description
Magneto-transport and magneto-optical properties of delta-doped InP near the metal-insulator transition
Author: Xiaomei Feng-Brames
Publisher:
ISBN:
Category :
Languages : de
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : de
Pages :
Book Description
Magneto-transport and Magneto-optical Properties of D-doped InP Near the Metal Insulator Transition
Author: Xiaomei Feng- Brames
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Magneto-transport and magneto-optical properties of _d63-doped [delta-doped] InP near the metal insulator transition
Author: Xiaomei Feng-Brames
Publisher:
ISBN:
Category :
Languages : de
Pages : 125
Book Description
Publisher:
ISBN:
Category :
Languages : de
Pages : 125
Book Description
Transport and Magneto-optical Study of the Metal-insulator Transition in Heavily Doped Cadmium Sulfide
Author: Ronald Ira Feigenblatt
Publisher:
ISBN:
Category : Metal insulator semiconductors
Languages : en
Pages : 390
Book Description
Publisher:
ISBN:
Category : Metal insulator semiconductors
Languages : en
Pages : 390
Book Description
Chemical Abstracts
Author:
Publisher:
ISBN:
Category : Chemistry
Languages : en
Pages : 2540
Book Description
Publisher:
ISBN:
Category : Chemistry
Languages : en
Pages : 2540
Book Description
Magnetic and Magneto-optical Properties of Doped Oxides
Author: Mohammed Alqahtani
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
This thesis describes the growth, structural characterisation, magnetic and magneto-optics properties of lanthanum strontium manganite (LSMO), GdMnO3 and transition metal (TM)-doped In2O3 thin films grown under different conditions. The SrTiO3 has been chosen as a substrate because its structure is suitable to grow epitaxial LSMO and GdMnO3 films. However, the absorption of SrTiO3 above its band gap at about 3.26 eV is actually a limitation in this study. The LSMO films with 30% Sr, grown on both SrTiO3 and sapphire substrates, exhibit a high Curie temperature (Tc) of 340 K. The magnetic circular dichroism (MCD) intensity follows the magnetisation for LSMO on sapphire; however, the measurements on SrTiO3 were dominated by the birefringence and magneto-optical properties of the substrate. In the GdMnO3 thin films, there are two well-known features in the optical spectrum; the charge transfer transition between Mn d states at 2 eV and the band edge transition from the oxygen p band to d states at about 3 eV; these are observed in the MCD. This has been measured at remanence as well as in a magnetic field. The optical absorption at 3 eV is much stronger than at 2 eV, however, the MCD is considerably stronger at 2 eV. The MCD at 2 eV correlates well with the Mn spin ordering and it is very notable that the same structure appears in this spectrum, as is seen in LaMnO3. The results of the investigations of Co and Fe-doped In2O3 thin films show that TM ions in the films are TM2+ and substituted for In3+. The room temperature ferromagnetism observed in TM-doped In2O3 is due to the polarised electrons in localised donor states associated with oxygen vacancies. The formation of Fe3O4 nanoparticles in some Fe-doped films is due the fact that TM-doped In2O3 thin films are extremely sensitive to the growth method and processing condition. However, the origin of the magnetisation in these films is due to both the Fe-doped host matrix and also to the nanoparticles of Fe3O4.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
This thesis describes the growth, structural characterisation, magnetic and magneto-optics properties of lanthanum strontium manganite (LSMO), GdMnO3 and transition metal (TM)-doped In2O3 thin films grown under different conditions. The SrTiO3 has been chosen as a substrate because its structure is suitable to grow epitaxial LSMO and GdMnO3 films. However, the absorption of SrTiO3 above its band gap at about 3.26 eV is actually a limitation in this study. The LSMO films with 30% Sr, grown on both SrTiO3 and sapphire substrates, exhibit a high Curie temperature (Tc) of 340 K. The magnetic circular dichroism (MCD) intensity follows the magnetisation for LSMO on sapphire; however, the measurements on SrTiO3 were dominated by the birefringence and magneto-optical properties of the substrate. In the GdMnO3 thin films, there are two well-known features in the optical spectrum; the charge transfer transition between Mn d states at 2 eV and the band edge transition from the oxygen p band to d states at about 3 eV; these are observed in the MCD. This has been measured at remanence as well as in a magnetic field. The optical absorption at 3 eV is much stronger than at 2 eV, however, the MCD is considerably stronger at 2 eV. The MCD at 2 eV correlates well with the Mn spin ordering and it is very notable that the same structure appears in this spectrum, as is seen in LaMnO3. The results of the investigations of Co and Fe-doped In2O3 thin films show that TM ions in the films are TM2+ and substituted for In3+. The room temperature ferromagnetism observed in TM-doped In2O3 is due to the polarised electrons in localised donor states associated with oxygen vacancies. The formation of Fe3O4 nanoparticles in some Fe-doped films is due the fact that TM-doped In2O3 thin films are extremely sensitive to the growth method and processing condition. However, the origin of the magnetisation in these films is due to both the Fe-doped host matrix and also to the nanoparticles of Fe3O4.
Magneto and Spin Transport in Magnetically Doped Semiconductors and Magnetic Insulators
Author: Zihao Yang
Publisher:
ISBN:
Category : Electrical engineering
Languages : en
Pages : 174
Book Description
Over the last two decades, spin transistors that operate using both charge and spin properties of electrons have motivated extensive studies of injection, detection and manipulation of electronic spin current in various material systems. Dilute magnetic semiconductors, in which the spin polarized charge carriers are coupled to the magnetic moment, are of particular interest due to their compatible lattice structures and similar growth methods to current Si and GaAs technology. The first part of this thesis focuses on the structural, magnetic and magnetotransport properties of magnetically doped GaN and 2D MoS2. The Gd doped AlN/GaN heterostructures are grown by plasma assisted molecular beam epitaxy. The Gd atoms are [delta]-doped at the AlN/GaN heterointerface where the two dimensional electron gas (2DEG) forms. These samples exhibit defect-induced room temperature ferromagnetism with an easy axis along the c-axis. However, the nonlinear Hall resistivity does not track the magnetization in these Gd doped samples indicating the lack of coupling between the conduction electrons in the 2DEG and the Gd-induced ferromagnetism. This makes Gd doped GaN not useful as a dilute magnetic semiconductor. Mn doped few-layer MoS2 samples synthesized via sulfurization of Mn thin film on sapphire are fabricated in the aim of realizing a 2D dilute magnetic semiconductor. However, these samples mainly show paramagnetism implying the lack of ferromagnetic coupling between the Mn dopants.
Publisher:
ISBN:
Category : Electrical engineering
Languages : en
Pages : 174
Book Description
Over the last two decades, spin transistors that operate using both charge and spin properties of electrons have motivated extensive studies of injection, detection and manipulation of electronic spin current in various material systems. Dilute magnetic semiconductors, in which the spin polarized charge carriers are coupled to the magnetic moment, are of particular interest due to their compatible lattice structures and similar growth methods to current Si and GaAs technology. The first part of this thesis focuses on the structural, magnetic and magnetotransport properties of magnetically doped GaN and 2D MoS2. The Gd doped AlN/GaN heterostructures are grown by plasma assisted molecular beam epitaxy. The Gd atoms are [delta]-doped at the AlN/GaN heterointerface where the two dimensional electron gas (2DEG) forms. These samples exhibit defect-induced room temperature ferromagnetism with an easy axis along the c-axis. However, the nonlinear Hall resistivity does not track the magnetization in these Gd doped samples indicating the lack of coupling between the conduction electrons in the 2DEG and the Gd-induced ferromagnetism. This makes Gd doped GaN not useful as a dilute magnetic semiconductor. Mn doped few-layer MoS2 samples synthesized via sulfurization of Mn thin film on sapphire are fabricated in the aim of realizing a 2D dilute magnetic semiconductor. However, these samples mainly show paramagnetism implying the lack of ferromagnetic coupling between the Mn dopants.
Physics Briefs
Author:
Publisher:
ISBN:
Category : Physics
Languages : en
Pages : 1058
Book Description
Publisher:
ISBN:
Category : Physics
Languages : en
Pages : 1058
Book Description
The Effect of Nonmagnetic Doping and Growth Temperature on the Magneto-transport Properties of Mangenese [sic] and Cobalt Doped Zinc Oxide Dilute Magnetic Semiconductors
Author: Govind Mundada
Publisher:
ISBN:
Category : Diluted magnetic semiconductors
Languages : en
Pages : 192
Book Description
Publisher:
ISBN:
Category : Diluted magnetic semiconductors
Languages : en
Pages : 192
Book Description