Ga1-xGdxN-Based Spin Polarized Light Emitting Diode

ABSTRACTIn this work, a room temperature spin-polarized LED based on ferromagnetic Ga1-xGdxN is reported. The device was grown by metalorganic chemical vapor deposition (MOCVD) and is the first report of a spin-LED based on Ga1-xGdxN. Electroluminescence from this device had a degree of polarization of 14.6% at 5000 Gauss and retained a degree of polarization of 9.3% after removal of the applied magnetic field. Ga1-xGdxN thin films were grown on 2 μm GaN templates and were co-doped with Si and Mg to achieve n-type and p-type materials. Co-doping of the Ga1-xGdxN films with Si produced conductive n-type material, while co-doping with Mg produced compensated p-type material. Both Si and Mg co-doped films exhibited room temperature ferromagnetism, measured by vibrating sample magnetometry.

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The Structural, Electrical, Magnetic Properties of (Cu, Co) Co-Doped ZnO Thin Film

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.556-562.429 ◽

2014 ◽

Vol 556-562 ◽

pp. 429-432

Author(s):

Ping Cao ◽

Yue Bai ◽

Zhi Qu

Keyword(s):

Room Temperature ◽

Room Temperature Ferromagnetism ◽

Sol Gel ◽

Hall Effect Measurement ◽

Ferromagnetic Semiconductors ◽

Zno Thin Film ◽

Zno Film ◽

Co Doping ◽

Doped Zno ◽

Co Doped

Successful synthesis of room-temperature ferromagnetic semiconductors, (Cu, Co) co-doped ZnO film is obtained by sol-gel method. It is found that the essential ingredient in achieving room-temperature ferromagnetism is Cu co-doping. By Hall-effect measurement ap-type conductivity was observed for the Cu co-doped films, which induced the room-temperature ferromagnetism.

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Spin-Polarized Room Temperature Ferromagnetism in Co-doped ZnO synthesized by Electrodeposition

Chinese Journal of Physics ◽

10.1016/j.cjph.2021.08.012 ◽

2021 ◽

Author(s):

Santosh Kumar ◽

Deepika ◽

Raju Kumar ◽

Ritesh Kumar ◽

Pratyush Vaibhav ◽

...

Keyword(s):

Room Temperature ◽

Room Temperature Ferromagnetism ◽

Spin Polarized ◽

Doped Zno ◽

Co Doped

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Room-Temperature Spin-Transport Properties in an In0.5Ga0.5As Quantum Dot Spin-Polarized Light-Emitting Diode

Physical Review Applied ◽

10.1103/physrevapplied.16.014034 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Kohei Etou ◽

Satoshi Hiura ◽

Soyoung Park ◽

Kazuya Sakamoto ◽

Junichi Takayama ◽

...

Keyword(s):

Quantum Dot ◽

Transport Properties ◽

Room Temperature ◽

Spin Transport ◽

Light Emitting Diode ◽

Polarized Light ◽

Light Emitting ◽

Spin Polarized

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Room temperature ferromagnetism in Co-doped amorphous carbon composites from the spin polarized semiconductor band

Applied Physics Letters ◽

10.1063/1.4892561 ◽

2014 ◽

Vol 105 (5) ◽

pp. 052410 ◽

Cited By ~ 2

Author(s):

H. S. Hsu ◽

P. C. Chien ◽

S. J. Sun ◽

Y. Y. Chang ◽

C. H. Lee

Keyword(s):

Amorphous Carbon ◽

Room Temperature ◽

Room Temperature Ferromagnetism ◽

Carbon Composites ◽

Spin Polarized ◽

Co Doped

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Magnetotransport Properties of MnGeAs2 Films

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.864.116 ◽

2017 ◽

Vol 864 ◽

pp. 116-120

Author(s):

Yun Ki Kim ◽

J.B. Ketterson

Keyword(s):

Thin Films ◽

Room Temperature ◽

Room Temperature Ferromagnetism ◽

Anomalous Hall Effect ◽

Current Voltage ◽

Spin Polarized ◽

Current Voltage Characteristics ◽

Small Change ◽

P Type ◽

Effective Carrier

MnGeAs2 thin films were successfully deposited on GaAs(100) substrate. The films exhibited room-temperature ferromagnetism with TC ~ 330 K, based on both magnetization and resistance measurements at temperatures from 5 to 370 K. The coercive fields at 5 and 300 K were 2100 and 50 Oe. The anomalous Hall effect was observed, suggesting the existence of spin polarized carriers in MnGeAs2 thin films. The magnetoresistance (MR) measurements showed very small change (~ 0.1% at 5 K) in resistance at low temperature. The MR value at 5 K was smaller than that (~ 9% at 305 K) at room temperature (305 K). Type of majority carriers in the films was determined to be n-type by Hall measurement above the transition temperature. The effective carrier density was 1.8´1020 cm-3. The diode current-voltage characteristics were shown in a hetero-junction MnGeAs2 film on a conducting p-type GaAs substrate.

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Increased room temperature ferromagnetism in Co-doped tetrahedral perovskite niobates

Royal Society Open Science ◽

10.1098/rsos.210121 ◽

2021 ◽

Vol 8 (10) ◽

Author(s):

Yi Zhou ◽

Qing He ◽

Fei Zhou ◽

Xingqi Liao ◽

Yong Liu ◽

...

Keyword(s):

Room Temperature ◽

Magnetic Semiconductors ◽

Room Temperature Ferromagnetism ◽

Dilute Magnetic Semiconductors ◽

Defect Band ◽

Co Doping ◽

Band Absorption ◽

Local Spin Polarization ◽

Curie Temperatures ◽

Co Doped

Dilute magnetic semiconductors (DMSs), such as (In, Mn)As and (Ga, Mn)As prototypes, are limited to III–V semiconductors with Curie temperatures ( T c ) far from room temperature, thereby hindering their wide application. Here, one kind of DMS based on perovskite niobates is reported. BaM x Nb (1− x ) O 3− δ ( M = Fe, Co) powders are prepared by the composite-hydroxide-mediated method. The addition of M elements endows BaM x Nb (1− x ) O 3− δ with local ferromagnetism. The tetragonal BaCo x Nb (1− x ) O 3− δ nanocrystals can be obtained by Co doping, which shows strong saturation magnetization ( M sat ) of 2.22 emu g −1 , a remnant magnetization ( M r ) of 0.084 emu g −1 and a small coercive field ( H c ) of 167.02 Oe at room temperature. The ab initio calculations indicate that Co doping could lead to a 64% local spin polarization at the Fermi level ( E F ) with net spin DOS of 0.89 electrons eV −1 , this result shows the possibility of maintaining strong ferromagnetism at room temperature. In addition, the trade-off effect between the defect band absorption and ferromagnetic properties of BaM x Nb (1− x ) O 3− δ is verified experimentally and theoretically.

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ROOM TEMPERATURE FERROMAGNETISM IN (N, Co)-CODOPED ZnO THIN FILMS

Modern Physics Letters B ◽

10.1142/s0217984907013195 ◽

2007 ◽

Vol 21 (13) ◽

pp. 799-806 ◽

Cited By ~ 3

Author(s):

D. L. HOU ◽

X. J. YE ◽

H. J. MENG ◽

X. Y. ZHAO ◽

H. J. ZHOU ◽

...

Keyword(s):

Thin Films ◽

Room Temperature ◽

Room Temperature Ferromagnetism ◽

Inverse Correlation ◽

Zno Thin Films ◽

Clear Correlation ◽

Ferromagnetic Property ◽

Glass Substrates ◽

P Type ◽

Co Doped

A series of nitrogen-doped Zn 0.93 Co 0.07 O thin films grown on glass substrates were prepared by magnetron sputtering, which have shown ferromagnetic property at room temperature. The largest moment of about 4.92 μB/ Co and Curie temperature (T c ) of about 300 K were observed for Zn 0.93 Co 0.07 O thin film. P-type Co -doped ZnO thin films with room temperature ferromagnetism were obtained. We demonstrated a clear correlation between nitrogen and transition temperature and an inverse correlation between nitrogen and magnetization per Co ion.

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Defects related room temperature ferromagnetism in p-type (Mn, Li) co-doped ZnO films deposited by reactive magnetron sputtering

Applied Surface Science ◽

10.1016/j.apsusc.2009.10.086 ◽

2010 ◽

Vol 256 (8) ◽

pp. 2453-2457 ◽

Cited By ~ 28

Author(s):

C.W. Zou ◽

H.J. Wang ◽

M.L. Yi ◽

M. Li ◽

C.S. Liu ◽

...

Keyword(s):

Magnetron Sputtering ◽

Room Temperature ◽

Room Temperature Ferromagnetism ◽

Reactive Magnetron Sputtering ◽

Zno Films ◽

Reactive Magnetron ◽

Doped Zno ◽

P Type ◽

Co Doped

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Chiral-induced spin selectivity enables a room-temperature spin light-emitting diode

Science ◽

10.1126/science.abf5291 ◽

2021 ◽

Vol 371 (6534) ◽

pp. 1129-1133

Author(s):

Young-Hoon Kim ◽

Yaxin Zhai ◽

Haipeng Lu ◽

Xin Pan ◽

Chuanxiao Xiao ◽

...

Keyword(s):

Magnetic Fields ◽

Room Temperature ◽

Light Emitting Diode ◽

Polarized Light ◽

Chiral Molecules ◽

Circularly Polarized Light ◽

Light Emitting ◽

Circularly Polarized ◽

Spin Polarized ◽

Spin Led

In traditional optoelectronic approaches, control over spin, charge, and light requires the use of both electrical and magnetic fields. In a spin-polarized light-emitting diode (spin-LED), charges are injected, and circularly polarized light is emitted from spin-polarized carrier pairs. Typically, the injection of carriers occurs with the application of an electric field, whereas spin polarization can be achieved using an applied magnetic field or polarized ferromagnetic contacts. We used chiral-induced spin selectivity (CISS) to produce spin-polarized carriers and demonstrate a spin-LED that operates at room temperature without magnetic fields or ferromagnetic contacts. The CISS layer consists of oriented, self-assembled small chiral molecules within a layered organic-inorganic metal-halide hybrid semiconductor framework. The spin-LED achieves ±2.6% circularly polarized electroluminescence at room temperature.

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ROOM-TEMPERATURE FERROMAGNETIC PROPERTIES OF Co-DOPED ZnO NAOROD ARRAYS

International Journal of Modern Physics B ◽

10.1142/s0217979213620105 ◽

2013 ◽

Vol 27 (15) ◽

pp. 1362010 ◽

Cited By ~ 2

Author(s):

C. L. ZHANG ◽

C. G. HU

Keyword(s):

Room Temperature ◽

Room Temperature Ferromagnetism ◽

Ferromagnetic Behavior ◽

Secondary Phases ◽

X Ray Diffraction ◽

Polarized Electrons ◽

Spin Polarized ◽

Doped Zno ◽

Zinc Foils ◽

Co Doped

Co -doped ZnO rod arrays were fabricated on zinc foils by a hydrothermal method. X-ray diffraction results indicate that the samples have wurtzite crystalline structure without metallic Co or other secondary phases detected. The nanorod arrays exhibit room-temperature ferromagnetic behavior for different Co concentration. The influence of Co on the magnetic properties of ZnO was studied by the first-principles calculations. The exchange interaction between local spin-polarized electrons and conductive electrons is proposed as a cause of the room-temperature ferromagnetism.

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