Hongxiang Wei
Personal Introduction
He is a doctor of science researcher, member of Institute of physics, Chinese Academy of Sciences, director of Science Popularization Committee of Chinese physical society, and executive deputy director of Yangtze River Delta Research Center, Institute of physics, Chinese Academy of Sciences. He is mainly engaged in the research of magnetism and magnetic materials, and has made a series of research achievements in high frequency spin nano oscillator, high density nonvolatile magnetic memory, super sensitive magnetic sensor and so on. He has presided over and participated in more than 20 scientific research projects of the Ministry of science and technology, the NSFC and the Academy of Sciences, published more than 60 academic papers, obtained more than 30 Chinese invention patents, and won the first prize of Beijing Science and Technology Award for some research achievements.Representative work
1、 Design and fabrication of a novel magnetic random access memory (MRAM) based on nano magnetic tunnel junction.
At the beginning, I participated in the whole process of designing and preparing traditional MRAM. The MRAM principle device designed and prepared by our research group is based on the domestic strength, which realizes the design and preparation of CMOS, the fine polishing of metal layer on the surface of CMOS, the integration and test of magnetic tunnel junction, the bonding and packaging of samples, and the performance test of samples. The test results show that the main technical parameters meet the design requirements. In particular, in the process of in-depth study and preparation of traditional MRAM, we proposed a new type of MRAM based on nano ring magnetic tunnel junction. A ring-shaped magnetic tunnel junction with a diameter of 100 nm and a wall width of 25-30 nm was prepared. This is the narrowest annular magnetic tunnel junction by far. The driving current is less than 1 mA. This research provides a new way for the development of high-density MRAM, and is highly praised by international peers.
2、 Preparation and research of high performance magnetic tunnel junction.
At first, by optimizing the process conditions, the magnetic tunnel junctions with a magnetoresistance ratio of 80% were fabricated by magnetron sputtering equipment in our laboratory. This result maintains the best result of magnetic tunnel junction with alumina as barrier layer. At the same time, we also have a good accumulation in the preparation of vertical anisotropic magnetic tunnel junction, double barrier magnetic tunnel junction, linear magnetic field response magnetic tunnel junction and nano scale magnetic tunnel junction.
3、 Design, preparation and research of nanostructure patterns.
In the beginning, micro processing equipment such as focused ion beam etching (FIB), electron beam lithography (EBL), chemical reaction etching (RIE), argon ion beam etching (AIE) are used to prepare holes with a diameter of 3-5 nm, a lattice with a diameter of 10-30 nm, and wires, rings and elliptical rings with a width of 10-50 nm. At the same time, we also carry out the design and preparation of some more complex nano patterns.
Honor
At the beginning of his doctorate, he received many awards from the Academy of Sciences. He is the winner of director scholarship excellent award and "three good student model" title of Graduate School of Chinese Academy of Sciences. He is also a scholarship winner of Chinese Academy of Sciences bhbp (Australia). He was supported by the scientific and technological innovation research project of Chinese Academy of Sciences and sponsored by IEEE association to attend academic conferences in the United States. He was awarded the outstanding graduate of Chinese Academy of Sciences for his outstanding performance during his doctoral period.
Representative works
W. J. Li, I. Bykova, S. L. Zhang, G. Q. Yu, * R. Tomasello, M. Carpentieri, Y. Z. Liu, Y. Guang, J. Grafe, M. Weigand, D. M. Burn, G. V. D. Laan, T. Hesjedal, Z. R. Yan, J. F. Feng, C. H. Wan, J. W. Wei, X. Wang, X. M. Zhang, H. J. Xu, C. Y. Guo, H. X. Wei, G. Finocchio, * X. F. Han and G. Schütz Adv. Mater. 31 (2019) 1807683
[56] Thermally activated magnetization backhopping based true random number generator in nano-ring magnetic tunnel junctions
J. Y. Qin, X. Wang, T. Qu, C. H. Wan, L. Huang, C. Y. Guo, T. Yu, H. X. Wei and X. F. Han*
Appl. Phys. Lett. 114 (2019) 112401 (Editors' Suggestion)
[55] Coherent Resonant Tunneling through Double Metallic Quantum Well States
B. S. Tao, C. H. Wan, P. Tang, J. F. Feng, H. X. Wei, X. W, S. Andrieu, H. X. Yang, M. B. Chshiev, X. Devaux, T. Hauet, F. Montaigne, S. Mangin, M. Hehn, D. Lacour, X. F. Han, and Y. Lu
Nano Letters 19 (2019) 3019
[54] Current-driven magnetization switching in a van der Waals ferromagnet Fe3GeTe2
X. Wang, J. Tang, X. X. Xia, C. L. He, J. W. Zhang, Y. Z. Liu, C. H. Wan, C. Fang, C. Y. Guo, W. L. Yang, Y. Guang, X. M. Zhang, H. J. Xu, J. W. Wei, M. Z. Liao, X. B. Lu, J. F. Feng, X. X. Li, Y. Peng, H. X. Wei, R. Yang, D. X. Shi, X. X. Zhang, Z. Han,* Z. D. Zhang, G. Y. Zhang,* G. Q. Yu,* X. F. Han
Sci. Adv. 5, eaaw8904 (2019)
[53] Tunneling anisotropic magnetoresistance in fully epitaxial MTJs with different barriers
B. S. Tao, L. N. Jiang, W. J. Kong, W. Z. Chen, B. S. Yang, X. Wang, C. H. Wan, H. X. Wei, M. Hehn, D. Lacour, Y. Lu* and X. F. Han*
Appl. Phys. Lett. 112 (2018) 242404
[52] Magnetic Configurations and State Diagram of Nanoring Magnetic Tunnel Junctions
H. F. Liu, H. X. Wei, X. F. Han, G. Q. Yu, W. S. Zhan, S. L. Gall, Y. Lu, M. Hehn,S. Mangin, M. J. Sun, Y. W. Liu, and C. Horng
Phys. Rev. Appl. 10 (2018) 054013
[51] Microwave Spin-Torque-Induced Magnetic Resonance in a Nanoring-Shape-Confined MTJs
J. Y. Qin, X. Chen, T. Yu, X. Wang, C. Y. Guo, C. H. Wan, J. F. Feng, H. X. Wei, Y. W. Liu and X. F. Han*
Phys. Rev. Appl. 10 (2018) 044067
[50] Magnon valve effect between two magnetic insulators
H. Wu, L. Huang, C. Fang, B. Yang, C. H. Wan, G. Yu, J. Feng, H. Wei, X. F. Han*
Phys. Rev. Lett. 120 (2018) 097205 (Editors' Suggestion, Featured in Physics)
[49] Temperature dependence of spin-torque driven ferromagnetic resonance in MgO-based magnetic tunnel junction with a perpendicularly free layer
X. Wang, J. F. Feng, P. Guo, H. X. Wei, X. F. Han*, B. Fang, Z. M. Zeng
J. Magn. Magn. Mater. 443 (2017) 239
[48] Giant Perpendicular Exchange Bias in a Subnanometer Inverted (Co/Pt)n/Co/IrMn Structure
J.F. Feng, H.F. Liu, H. X. Wei, X.-G. Zhang,Y. Ren, X.X. Li, Y. Wang, J.P. Wang, X. F. Han
Phys. Rev. Appl. 7 (2017) 054005
[47] Magneto-Seebeck effect in magnetic tunnel junctions with perpendicular anisotropy
K. Y. Ning, H. F. Liu, Z. Y. Ju, C. Fang, C. H. Wan, J. L. Cheng, X. Liu, L. S. Li, J. F. Feng, H. X. Wei, X. F. Han, Y. Yang, T. L. Ren
AIP Adv. 7 (2017) 015035
[46] Tailoring perpendicular magnetic anisotropy with graphene oxide membranes
K. Y. Ning, H. F. Liu, L. S. Li, H. L. Li, J. F. Feng, B. S. Yang, X. Liu, Y. X. Li, Y. H. Chen, H. X. Wei, X. F. Han, S. C. Mao, X. X. Zhang, Y. Yang, T. L. Ren
RSC Adv. 7 (2017) 52938
[45] Observation of magnon-mediated electric current drag at room temperature
H. Wu, C.H. Wan, X. Zhang, Z. Yuan, Q. Zhang, J. Qin, H. Wei, X. F. Han*, S. Zhang*
Phys. Rev. B 93 (2016) 060403(R)
[44] Temperature dependence of microwave oscillations in magnetic tunnel junctions with a perpendicularly magnetized free layer
P. Guo, J. F. Feng*, H. X. Wei*, X. F. Han, B. Fang, B. S. Zhang, and Z. M. Zeng*
Appl. Phys. Lett. 106 (2015) 012402
[43] Effect of interfacial structures on spin dependent tunneling in epitaxial L10- FePt/MgO/FePt perpendicular magnetic tunnel junctions
G. Yang, D. L. Li, S. G. Wang*, Q. L. Ma, S. H. Liang, H. X. Wei, X. F. Han, T. Hesjedal, R. C. C. Ward, A. Kohn, A. Elkayam, N. Tal, and X.-G. Zhang
Journal of Applied Physics 117 (2015) 083904
[42] Manipulation of Tunnel Magnetoresistance via temperature and voltage control
H. F. Liu, R. Wang, P. Guo, Z. C. Wen, J.F. Feng, H. X. Wei, X. F. Han*, Y. Ji, S. Zhang*
Scientific reports. 5 (2015)18269
[41] Transport Properties in Sputtered CoFeB/MgAl2O4/CoFeB Magnetic Tunnel Junction
B. S. Tao, D. L. Li, H. F. Liu, H. X. Wei, J. F. Feng, S. G. Wang, and X. F. Han*
IEEE Transactions on Magnetics 50 (2014) 4401004
[40] Perpendicular magnetic anisotropy in Ta|Co40Fe40B20|MgAl2O4 structures and perpendicular CoFeB|MgAl2O4|CoFeB magnetic tunnel junction
B. S. Tao, D. L. Li, Z. H. Yuan, H. F. Liu, S. S. Ali, J. F. Feng, H. X. Wei, X. F. Han*, Y. Liu, Y. G. Zhao, Q. Zhang, Z. B. Guo, and X. X. Zhang
Appl. Phys. Lett. 105 (2014) 102407
[39] Tunneling magnetoresistance in Fe3Si/MgO/Fe3Si(001) magnetic tunnel junctions
L. L. Tao, S. H. Liang, D. P. Liu, H. X. Wei, J. Wang, and X. F. Han*
Appl. Phys. Lett. 104 (2014) 172406
[38] Nonlinear temperature dependent nucleation field in perpendicular exchange spring typed magnetic tunnel junctions
Yi Wang, D. Le Roy, Jun Jiang, Xiaolu Yin, H. X. Wei, S. H. Liou, and X. F. Han
J. Appl. Phys. 113 (2013) 17C113
[37] Magnetization reversal and enhanced tunnel magneto resistance ratio in perpendicular magnetic tunnel junctions based on exchange spring electrodes
Yi Wang, Xiaolu Yin, D. Le Roy, Jun Jiang, H. X. Wei, S. H. Liou, and X. F. Han
J. Appl. Phys. 113 (2013) 133906
[36] MgO-Based Double Barrier MTJs With Synthetic Antiferromagnetic Free Layer
D. L. Li, J. F. Feng, G. Q. Yu, H. X. Wei, X. F. Han, and J. M. D. Coey
IEEE Trans. Magn. 49 (2013) 5204
[35] Low frequency noise in magnetic tunneling junctions with Co40Fe40B20/Co70.5Fe4.5Si15B10 composite free layer
Z. H. Yuan, J. Feng, P. Guo, C. H. Wan, H.X. Wei, S.S. Ali, X. F. Han*, T. Nakano, H. Naganuma, and Y. Ando
Journal of Magnetism and Magnetic Materials 398 (2015) 215
[34] Controlling spin-dependent tunneling by bandgap tuning in epitaxial rocksalt MgZnO films
D. L. Li, Q. L. Ma, S. G. Wang*, R. C. C. Ward, T. Hesjedal, X.-G. Zhang, A. Kohn, E. Amsellem, G. Yang, J. L. Liu, J. Jiang, H. X. Wei and X. F. Han
Sci. Rep. 4 (2014) 7277
[33] Tunneling processes in asymmetric double barrier magnetic tunnel junctions with a thin top MgO layer
D. L. Li, J. F. Feng, G. Q. Yu, P. Guo, J. Y. Chen, H. X. Wei, X. F. Han, and J. M. D. Coey
J. Appl. Phys. 114 (2013) 213909
[32] Evidence for magnon excitation contribution to the magnetoresistance behavior during thermal annealing in CoFeB/MgO/CoFeB magnetic tunnel junctions
Q. L. Ma, S. G. Wang, H. X. Wei, H. F. Liu, X.-G. Zhang, and X. F. Han
Phys. Rev. B 83 (2011) 224430
[31] Nanoelliptic Ring-Shaped Magnetic Tunnel Junction and Its Application in MRAM Design with Spin-Polarized Current Switching (Invited paper)
X. F. Han, Z. C. Wen, Y. Wang, H. F. Liu, H. X. Wei, D. P. Liu
IEEE Trans. Magn. 47 (2011) 2957 .
[30] Patterned Nanoscale Magnetic Tunnel Junctions with Different Geometry Structures
Z. C. Wen, Y. Wang, G. Q. Yu, H. X. Wei, B. S. Zhang, K. Xu, and X. F. Han
Spin 1 (2011) 109
[29] Signatures of surface magnon and impurity scatterings in tunnel junctions
H. X. Wei, Q. H. Qin, Q. L. Ma, X.G. Zhang and X. F. Han*
Phys. Rev. B 82 (2010) 134436
[28] Effect of annealing on the MTJ with Co/Pt perpendicular anisotropy ferromagnetic multilayers
Yi. Wang, W. X. Wang, H. X. Wei, B. S. Zhang, W. S. Zhan, and X. F. Han*
J. Appl. Phys.107 (2010) 09C711
[27] Cotunneling enhancement of magnetoresistance in double magnetic tunnel junctions with embedded superparamagnetic NiFe nanoparticles
K.J. Dempsey, A. T. Hindmarch, H.-X. Wei, Q.-H. Qin, Z.-C. Wen, W.-X. Wang, G.Vallejo-Fernandez, D. A. Arena, X. F. Han, and C. H. Marrows
Phys. Rev. B 82 (2010) 214415
[26] Giant Coulomb blockade magnetoresistance (CBMR) in MTJs with a granular layer
X. -G. Zhang, Z. C. Wen, H. X. Wei, and X. F. Han
Phys. Rev. B 81 (2010) 155122
[25] Structural and magnetic changes in MgO-based MTJs during the early stages of annealing.
R. I. G. Anderson, H. X. Wei, N. Porter, D. Arena, J. Dvorak, X. F. Han, C.H. Marrows
J. Magn. Magn. Mater. 322 (2010) 756-761
[24] Changes in the layer roughness and crystallography during the annealing of CoFeB/MgO/CoFeB magnetic tunnel junctions.
G. I. R. Anderson, H. X. Wei, N. A. Porter, V. Harnchana, A. P. Brown, R. M. D. Brydson, D. A. Arena, J. Dvorak, X. F. Han, and C. H. Marrows
J. Appl. Phys. 105 (2009) 063904
[23] Magnetic tunnel junction sensor with Co/Pt perpendicular anisotropy ferromagnetic layer.
H. X. Wei, Q. H. Qin, Z. C. Wen, X. F. Han, and X. G. Zhang
Appl. Phys. Lett. 94 (2009) 172902
[22] Linear magnetic field response spin valve with perpendicular anisotropy ferromagnet layer
Q. H. Qin, H. X. Wei and X. F. Han*, et al.
J. Appl. Phys. 103 (2008) 07E906
[21] Surface plasmon polaritons assisted diffraction in metal films with subwave length hole array
X. Fang, H. X. Wei, M. Kamran, J. Y. Ma, H. Y. Zhao, X. F. Han, X. G. Qiu
J. Phys. Chem. Solids 69 (2008) 3093--3095
[20] Effects of the current on the nanoscale ring-shaped magnetic tunnel junctions
H. X. Wei, J. X. He, Z. C. Wen, X. F. Han*, S. Zhang.
Phys. Rev. B 77 (2008) 134432
[19] Current-induced magnetization switching in a microscale ring-shaped MTJ
H. X. Wei, M. C. Hickey, G. I. R. Anderson, X. F. Han, and Christopher H. Marrows
Phys. Rev. B 77 (2008) 132401
[18] Nanoring MTJ and its application in MRAM demo devices with spin-polarized current switching (Invited paper),
X. F. Han*, Z. C. Wen, and H. X. Wei, et al.
J. Appl. Phys. 103 (2008) 07E933
[17] Current-induced multiple spin structures in 100-nm nanoring magnetic tunnel junctions
H. X. Wei, F. Q. Zhu, X. F. Han*, Z. C. Wen, C. L. Chien
Phys. Rev. B 77 (2008) 224432
[16] Patterned nanoring magnetic tunnel junctions
Z. C. Wen, H. X. Wei, and X. F. Han*
Appl. Phys. Lett. 91 (2007) 122511
[15] An approach to fabricate pure metallic Ni-Ni and metallic oxide Ni-NiO-Ni nanocontacts by repeatable microfabrication method
H. X. Wei, T. X. Wang, H. Wang, X. F. Han*, M. A. Bari, and J. M. D. Coey
Int. J. Nanotechnology 4(1/2) (2007) 21-27
[14] 80% TMR at RT for thin Al–O barrier MTJs with CoFeB as free and reference layers
H. X. Wei, Q. H. Qin, M. Ma, R. Sharif, and X. F. Han*
J. Appl. Phys. 101 (2007) 09B501
[13] Surface-Plasmon-Polariton Assisted Diffraction in Periodic Subwavelength Holes of Metal Films with Reduced Interplane Coupling
X. Fang, Z.Y. Li, Y.B. Long, H.X. Wei, R.J. Liu, J.Y. Ma, M. Kamran, H.Y. Zhao, X.F. Han, B.R. Zhao, and X.G. Qiu*
Phys. Rev. Lett. 99 (2007) 066805
[12] A novel design and fabrication of MRAM based on nano-ring-type MTJs (Letter to Editor)
X. F. Han, H. X. Wei, Z. L. Peng, H. D. Yang, J. F. Feng, G. X. Du, Z. B. Sun, L. X. Jiang, Q. H. Qin, M. Ma, Y. Wang, Z. C. Wen, D. P. Liu, and W. S. Zhan
J. Mater. Sci. & Tech 23 (2007) 304
[11] Controlled Fabrication of Nickel Perpendicular Nanocontacts using Focused Ion beam Milling
H. X. Wei，R M. Langford，X. F. Han*, J. M. D. Coey
J. Appl. Phys. 99 (2006) 08C501
[10] Magnetoresistance nickel nanocontacts fabricated by three different methods.
H. X. Wei, T. X. Wang, X. F. Han*, R M. Langford, and J. M. D. Coey
J. Appl. Phys. 99 (2006) 08C512
[9] Controlled fabrication of nano-scale double barrier MTJs using focused ion beam milling method.
H. X. Wei, T. X. Wang, Z. M. Zeng, X. Q. Zhang, J. Zhao, X. F. Han*
J. Magn. Magn. Matter. 303 (2006) c219-c222
[8] High magnetoresistance in Co-Fe-B based double barrier magnetic tunnel junctions
Z. M. Zeng, H. X. Wei, L. X. Jiang, G. X. Du, W. S. Zhan, and X. F. Han*
J. Magn. Magn. Matter. 303 (2006) c208-c211
[7] Magnetic/nonmagnetic/magnetic tunnel junction based on hybrid organic LB-films
T. X. Wang, H. X. Wei, Z. M. Zeng, and X. F. Han*, Z. M. Hong and G. Q. Shi
Appl. Phys. Lett. 88 (2006) 242505
[6] A novel method of nanocontact fabrication for Andreev reflection measurement
T. X. Wang, H. X. Wei, C. Ren, X. F. Han*, E. Clifford, R. M. Langford, M.A. Bari, and J. M. D. Coey,
Chinese J. of Semiconductors 27(4) (2006) 619
[5] Perpendicular current-driven magnetization switching in free layer of MTJs and MRAM,
Z. L. Peng, X. F. Han, S.F. Zhao, H. X. Wei, G. X. Du, and W. S. Zhan
Acta Physica Sinica 55 (2) (2006) 860—864
[4] Spin transport in multi wall Carbon Nanotube with Co electrodes
T. X. Wang, H. X. Wei, X. F. Han*, X.G. Zhang, M.A. Bari, and J.M.D. Coey
Chinese Physics Letter 23 (10) (2006) 2852-2855
[3] Microfabrication methods of magnetic tunnel junctions with high TMR
F. F. Li, X. Q. Zhang, G. X. Du, T. X. Wang, Z. M. Zeng, H. X. Wei, X. F. Han
Acta Physica Sinica 54 (2005) 346
[2] Vortex domain structures and dc current dependence of magneto-resistances in MTJ
H. X. Wei, Q. F. Lu, S. F. Zhao, X. Q. Zhang, J. F. Feng and X. F. Han
Chinese Physics 13 (2004) 1553
[1] Microfabrication of magnetic tunnel junctions on 4-inch Si/SiO2 substrate
T. X. Wang, H. X. Wei, F. F. Li, A. G. Zhang, Z. M. Zeng, W. S. Zhan, X. F. Han
Acta Physica Sinica 53 (2004) 3895
Address: Beijing National Laboratory for Condensed Matter Physics No.8, 3rd South Street, Zhongguancun, Haidian District, Beijing 100190, China Code: 100190 Tel：+86-10-82649268 Fax：+86-10-82649485 Email：xfhan@iphy.ac.cn