Generating and reversing spin accumulation by temperature gradient in a quantum dot attached to ferromagnetic leads

Generating and reversing spin accumulation by temperature gradient in a quantum dot attached to ferromagnetic leads

导出

摘要 We propose to generate and reverse the spin accumulation in a quantum dot （QD） by using the temperature difference between the two ferromagnetic leads connected to the dot. The electrons are driven purely by the temperature gradient in the absence of an electric bias and a magnetic field. In the Coulomb blockade regime, we find two ways to reverse the spin accumulation. One is by adjusting the QD energy level with a fixed temperature gradient, and the other is by reversing the temperature gradient direction for a fixed value of the dot level. The spin accumulation in the QD can be enhanced by the magnitudes of both the leads＇ spin polarization and the asymmetry of the dot-lead coupling strengths. The present device is quite simple, and the obtained results may have practical usage in spintronics or quantum information processing. We propose to generate and reverse the spin accumulation in a quantum dot （QD） by using the temperature difference between the two ferromagnetic leads connected to the dot. The electrons are driven purely by the temperature gradient in the absence of an electric bias and a magnetic field. In the Coulomb blockade regime, we find two ways to reverse the spin accumulation. One is by adjusting the QD energy level with a fixed temperature gradient, and the other is by reversing the temperature gradient direction for a fixed value of the dot level. The spin accumulation in the QD can be enhanced by the magnitudes of both the leads＇ spin polarization and the asymmetry of the dot-lead coupling strengths. The present device is quite simple, and the obtained results may have practical usage in spintronics or quantum information processing.

作者白旭芳迟锋郑军李亦楠

机构地区 College of Physics and Electronic Information College of Engineering SKLSM

出处《Chinese Physics B》 SCIE EI CAS CSCD 2012年第7期464-469,共6页 中国物理B（英文版）

基金 Project supported by the National Natural Science Foundation of China (Grant No. 10704011) the SKLSM, China (Grant No.CHJG200901) the LNET, China (Grant No. 2009R01)

关键词 quantum dot temperature gradient spin accumulation ferromagnetic leads quantum dot, temperature gradient, spin accumulation, ferromagnetic leads

分类号 O471.1 [理学—半导体物理] TG244.3 [金属学及工艺—铸造]

引文网络
相关文献

参考文献33

1Hanson R, Kouwenhoven L P, Petta J R, Tarucha S and Vandersypen L M K 2007 Rev. Mod. Phys. 79 1217.
2Loss D and DiVincenzo D P 1998 Phys. Rev. A 57 120.
3Liu P and Xiong S J 2009 Chin. Phys. B 18 5414.
4Koppens F H L, Buizerk C, Tielrooij K J, Vink I T, Nowack K C, Meunier T, Kouwenhoven L P and Vandersypen L M K 2006 Nature 442 766.
5PressD, Ladd T D, Zhang B Y and Yamamoto Y 2008 Nature 456 218.
6Greilich A, Economou S E, Spatzek S, Yakovlev D R, Reuter D, Wieck A D, Reinecke T L and Bayer M 2009 Nat. Phys. 5 262.
7Xu X D, Wu Y W, Sun B, Huang Q, Cheng J, Steel D G, Bracker A S, Gammon D, Emary C and Sham L J 2007 Phys. Rev. Lett. 99 097401.
8Ebbens A, Krizhanovskii D N, Tartakovskii A I, Pulizzi F, Wright T, Savelyev A V, Skolnick M S and Hopkinson M 2005 Phys. Rev. B 72 073307.
9Clark S M, Fu K M C, Ladd T D and Yamamoto Y 2007 Phys. Rev. Lett. 99 040501.
10Elzerman J M, Hanson R, Willems van Beveren L H, Witkamp B, Vandersypen L M K and Kouwenhoven L P 2004 Nature 430 431.

1FU Xi,ZHOU Guang-Hui.Spin Accumulation in a Rashba Nanoribbon[J].Communications in Theoretical Physics,2009,52(7):159-162.
2刘军,王琼,匡乐满,曾浩生.Distributed quantum information processing via quantum dot spins[J].Chinese Physics B,2010,19(3):76-82.
3吴照奇,朱传喜,张小芝.Some New Metrics Based on Partial Fidelity and Partial Super-Fidelity[J].Communications in Theoretical Physics,2014,61(1):37-39.
4XiChen,XinTao.Heat Transfer to a Particle Exposed to a Rarefied Plasma with a Great Temperature Gradient[J].Journal of Thermal Science,1993,2(2):135-142.
5Bao She WEI Department of Mathematics, Nanjing University. Nanjing 210093. P. R. China.Existence of Invariant Tori for Certain Weakly Reversible Mappings[J].Acta Mathematica Sinica,English Series,2002,18(4):701-718.
6LI Hong JIANG Zhan-Feng.Spin Accumulation of Spinor Atoms in Optical Lattices[J].Communications in Theoretical Physics,2007,47(5):777-780.
7刘佳,程杰.Thermal Bias on the Pumped Spin-Current in a Single Quantum Dot[J].Communications in Theoretical Physics,2014,61(7):86-90.
8尹海涛,吕天全,刘晓杰,薛惠杰.Spin Accumulation in a Double Quantum Dot Aharonov-Bohm Interferometer[J].Chinese Physics Letters,2009,26(4):199-202.
9LI Jian ZOU Jian SHAO Bin.Quantum Information Processing in a Coupled Cavity Array[J].Communications in Theoretical Physics,2008,50(12):1312-1316.
10刘晓石.OPERATION OF “INTERIOR” AND REGULARITY, NORMALITY OF POINTWISE TOPOLOGY ON COMPLETELY DISTRIBUTIVE LATTICES[J].Chinese Science Bulletin,1988,33(23):1928-1932.

Chinese Physics B

2012年第7期

浏览历史

内容加载中请稍等...

Generating and reversing spin accumulation by temperature gradient in a quantum dot attached to ferromagnetic leads

参考文献33

相关作者

相关机构

相关主题

浏览历史