Flexible Multiferroic Heterostructure Based on Freestanding Single‐Crystalline BaTiO 3 Membranes for Spintronic Devices

AbstractPure voltage-controlled magnetism, rather than a spin current or magnetic field, is the goal for next-generation ultralow power consumption spintronic devices. To advance toward this goal, we report a voltage-controlled nonvolatile 90° magnetization rotation and voltage-assisted 180° magnetization reversal in a spin-valve multiferroic heterostructure. Here, a spin valve with a synthetic antiferromagnetic structure was grown on a (110)-cut Pb(Mg1/3Nb2/3)0.7Ti0.3O3 (PMN-PT) substrate, in which only the magnetic moment of the free layer can be manipulated by an electric field (E-field) via the strain-mediated magnetoelectric coupling effect. As a result of selecting a specified PMN-PT substrate with defect dipoles, nonvolatile and stable magnetization switching was achieved by using voltage impulses. Accordingly, a giant, reversible and nonvolatile magnetoresistance modulation was achieved without the assistance of a magnetic field. In addition, by adopting a small voltage impulse, the critical magnetic field required for complete 180° magnetization reversal of the free layer can be tremendously reduced. A magnetoresistance ratio as large as that obtained by a magnetic field or spin current under normal conditions is achieved. These results indicate that E-field-assisted energy-efficient in-plane magnetization switching is a feasible strategy. This work is significant to the development of ultralow-power magnetoresistive memory and spintronic devices.

Download Full-text

“Preparation of Single Crystalline Gold Films for ED Studies”

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096424 ◽

1972 ◽

Vol 30 ◽

pp. 634-635

Author(s):

Joseph D. C. Peng

Keyword(s):

Crystal Morphology ◽

Diffraction Theory ◽

Scattering Matrix ◽

Vacuum Evaporation ◽

Gold Films ◽

Matrix Formulation ◽

Silver Films ◽

Single Crystalline ◽

Grating Pattern ◽

Stacking Disorder

The relative intensities of the ED spots in a cross-grating pattern can be calculated using N-beam electron diffraction theory. The scattering matrix formulation of N-beam ED theory has been previously applied to imperfect microcrystals of gold containing stacking disorder (coherent twinning) in the (111) crystal plane. In the present experiment an effort has been made to grow single-crystalline, defect-free (111) gold films of a uniform and accurately know thickness using vacuum evaporation techniques. These represent stringent conditions to be met experimentally; however, if a meaningful comparison is to be made between theory and experiment, these factors must be carefully controlled. It is well-known that crystal morphology, perfection, and orientation each have pronounced effects on relative intensities in single crystals.The double evaporation method first suggested by Pashley was employed with some modifications. Oriented silver films of a thickness of about 1500Å were first grown by vacuum evaporation on freshly cleaved mica, with the substrate temperature at 285° C during evaporation with the deposition rate at 500-800Å/sec.

Download Full-text

Recombination Characteristics of Single-Crystalline Silicon Wafers with a Damaged Near-Surface Layer

Ukrainian Journal of Physics ◽

10.15407/ujpe58.02.0142 ◽

2013 ◽

Vol 58 (2) ◽

pp. 142-150 ◽

Cited By ~ 1

Author(s):

A.V. Sachenko ◽

◽

V.P. Kostylev ◽

V.G. Litovchenko ◽

V.G. Popov ◽

...

Keyword(s):

Surface Layer ◽

Crystalline Silicon ◽

Silicon Wafers ◽

Single Crystalline Silicon ◽

Near Surface ◽

Single Crystalline

Download Full-text

Synthesis of Jumbo-size Single Crystalline Bi$lt;inf$gt;2$lt;/inf$gt;Se$lt;inf$gt;3$lt;/inf$gt; Nanoplates and Nanoribbons by Vapor Transportation

Journal of Inorganic Materials ◽

10.15541/jim20140087 ◽

2014 ◽

Vol 29 (11) ◽

pp. 1199

Author(s):

LI Xiao-Shuai ◽

WANG Zeng-Mei ◽

ZHU Ming-Fang ◽

WANG Shan-Peng ◽

TAO Xu-Tang ◽

...

Keyword(s):

Single Crystalline

Download Full-text

Formation of Large, Orientation-Controlled, Nearly Single Crystalline Si Thin Films on SiO2 Using Contact Printing of Rolled and Annealed Nickel Tapes

MRS Proceedings ◽

10.1557/proc-762-a17.13 ◽

2003 ◽

Vol 762 ◽

Author(s):

Hwang Huh ◽

Jung H. Shin

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

High Resolution ◽

Amorphous Silicon ◽

Tem Analysis ◽

Contact Printing ◽

Single Crystalline ◽

High Resolution Tem ◽

Lateral Crystallization ◽

Si Films

AbstractAmorphous silicon (a-Si) films prepared on oxidized silicon wafer were crystallized to a highly textured form using contact printing of rolled and annealed nickel tapes. Crystallization was achieved by first annealing the a-Si film in contact with patterned Ni tape at 600°C for 20 min in a flowing forming gas (90 % N2, 10 % H2) environment, then removing the Ni tape and further annealing the a-Si film in vacuum for2hrsat600°C. An array of crystalline regions with diameters of up to 20 μm could be formed. Electron microscopy indicates that the regions are essentially single-crystalline except for the presence of twins and/or type A-B formations, and that all regions have the same orientation in all 3 directions even when separated by more than hundreds of microns. High resolution TEM analysis shows that formation of such orientation-controlled, nearly single crystalline regions is due to formation of nearly single crystalline NiSi2 under the point of contact, which then acts as the template for silicide-induced lateral crystallization. Furthermore, the orientation relationship between Si grains and Ni tape is observed to be Si (110) || Ni (001)

Download Full-text