scholarly journals INFLUENCE OF SPIN-FLIP ON THE PERFORMANCE OF THE SPIN-DIODE

2011 ◽  
Vol 25 (30) ◽  
pp. 2335-2341 ◽  
Author(s):  
M. BAGHERI TAGANI ◽  
H. RAHIMPOUR SOLEIMANI

We study spin-dependent transport through a spin diode in the presence of spin-flip by means of reduced density matrix approach. The current polarization and the spin accumulation are computed and influence of spin-flip on the current polarization is also analyzed. Analytical relations for the current polarization and the spin accumulation are obtained as a function of polarization of ferromagnetic lead and the spin-flip rate. It is observed that the current polarization becomes zero under fast spin-flip and the spin accumulation decreases up to 85% when the time of spin-flip is equal to the tunneling time. It is also observed that the current polarization increases linearly when the dot is singly occupied, whereas its behavior is more complicated when the dot is doubly occupied.

2011 ◽  
Vol 25 (25) ◽  
pp. 2033-2039
Author(s):  
M. BAGHERI TAGANI ◽  
H. RAHIMPOUR SOLEIMANI

We study spin-dependent transport through a quantum dot with Zeeman split levels coupled to ferromagnetic leads and under influence of microwave irradiation. Current polarization, spin current, spin accumulation and tunneling magnetoresistance are analyzed using nonequilibrium Green's function formalism and rate equations. Spin-dependent beats in spin resolved currents are observed. The effects of magnetic field, temperature and Coulomb interaction on these beats are studied.


2008 ◽  
Vol 22 (05) ◽  
pp. 323-335
Author(s):  
KAI-HE DING ◽  
ZHEN-GANG ZHU ◽  
XING-HAI LIU

Based on the non-equilibrium Green function method, we investigate the spin-dependent transport through a finite interacting quantum dot with intradot spin-flip scattering for non-collinear configuration. It is found that when the intradot spin-flip scattering is applied, the Kondo peaks in the local density of states and the conductance are split, and the splitting peaks are suppressed sharply. By changing the relative orientation of both magnetizations, amplitudes of the splitting peaks appear asymmetric, and reduce with the increasing relative angle θ of the two magnetic moments. It is uncovered that the presence of the spin-flip scattering tends to greatly suppress the spin-valve effect.


2006 ◽  
Vol 358 (1) ◽  
pp. 47-52 ◽  
Author(s):  
Xi Chen ◽  
Hai-Feng Mu ◽  
Qing-Rong Zheng ◽  
Gang Su

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Yun Li ◽  
Xiaobo Li ◽  
Shidong Zhang ◽  
Liemao Cao ◽  
Fangping Ouyang ◽  
...  

AbstractStrain engineering has become one of the effective methods to tune the electronic structures of materials, which can be introduced into the molecular junction to induce some unique physical effects. The various γ-graphyne nanoribbons (γ-GYNRs) embedded between gold (Au) electrodes with strain controlling have been designed, involving the calculation of the spin-dependent transport properties by employing the density functional theory. Our calculated results exhibit that the presence of strain has a great effect on transport properties of molecular junctions, which can obviously enhance the coupling between the γ-GYNR and Au electrodes. We find that the current flowing through the strained nanojunction is larger than that of the unstrained one. What is more, the length and strained shape of the γ-GYNR serves as the important factors which affect the transport properties of molecular junctions. Simultaneously, the phenomenon of spin-splitting occurs after introducing strain into nanojunction, implying that strain engineering may be a new means to regulate the electron spin. Our work can provide theoretical basis for designing of high performance graphyne-based devices in the future.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Yipeng An ◽  
Kun Wang ◽  
Shijing Gong ◽  
Yusheng Hou ◽  
Chunlan Ma ◽  
...  

AbstractTwo-dimensional (2D) magnetic materials are essential for the development of the next-generation spintronic technologies. Recently, layered van der Waals (vdW) compound MnBi2Te4 (MBT) has attracted great interest, and its 2D structure has been reported to host coexisting magnetism and topology. Here, we design several conceptual nanodevices based on MBT monolayer (MBT-ML) and reveal their spin-dependent transport properties by means of the first-principles calculations. The pn-junction diodes and sub-3-nm pin-junction field-effect transistors (FETs) show a strong rectifying effect and a spin filtering effect, with an ideality factor n close to 1 even at a reasonably high temperature. In addition, the pip- and nin-junction FETs give an interesting negative differential resistive (NDR) effect. The gate voltages can tune currents through these FETs in a large range. Furthermore, the MBT-ML has a strong response to light. Our results uncover the multifunctional nature of MBT-ML, pave the road for its applications in diverse next-generation semiconductor spin electric devices.


2020 ◽  
Vol 126 (7) ◽  
Author(s):  
Qian Liu ◽  
Yaqiang Tian ◽  
Xiaoping Zheng ◽  
Liansheng Chen ◽  
Yuqing Zhao ◽  
...  

RSC Advances ◽  
2016 ◽  
Vol 6 (46) ◽  
pp. 40155-40161 ◽  
Author(s):  
Wei Wang ◽  
Yan-Dong Guo ◽  
Xiao-Hong Yan

Two-probe systems of transition metal atom (X)-encapsulated B40fullerene contacted with Au electrodes, where X = Fe, Mn, Ni, and Co.


Sign in / Sign up

Export Citation Format

Share Document