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Remote control of magnetostriction-based nanocontacts at room temperature.

Jammalamadaka SN, Kuntz S, Berg O, Kittler W, Kannan UM, Chelvane JA, Sürgers C - Sci Rep (2015)

Bottom Line: This can be achieved by exploiting the magnetostriction effects of ferromagnetic materials.Investigating the conductance in the regime of electron tunneling by mechanical or magnetostrictive control of the electrode separation enables an estimation of the magnetostriction.The present results pave the way to utilize the material in devices based on nano-electromechanical systems operating at room temperature.

View Article: PubMed Central - PubMed

Affiliation: Magnetic Materials and Device Physics Laboratory, Department of Physics, Indian Institute of Technology Hyderabad, Hyderabad 502 205, India.

ABSTRACT
The remote control of the electrical conductance through nanosized junctions at room temperature will play an important role in future nano-electromechanical systems and electronic devices. This can be achieved by exploiting the magnetostriction effects of ferromagnetic materials. Here we report on the electrical conductance of magnetic nanocontacts obtained from wires of the giant magnetostrictive compound Tb0.3Dy0.7Fe1.95 as an active element in a mechanically controlled break-junction device. The nanocontacts are reproducibly switched at room temperature between "open" (zero conductance) and "closed" (nonzero conductance) states by variation of a magnetic field applied perpendicularly to the long wire axis. Conductance measurements in a magnetic field oriented parallel to the long wire axis exhibit a different behaviour where the conductance switches between both states only in a limited field range close to the coercive field. Investigating the conductance in the regime of electron tunneling by mechanical or magnetostrictive control of the electrode separation enables an estimation of the magnetostriction. The present results pave the way to utilize the material in devices based on nano-electromechanical systems operating at room temperature.

No MeSH data available.


Related in: MedlinePlus

Texture and magnetostriction of Tb0.3Dy0.7Fe1.95.(a) X-ray diffraction pattern (Cu Kα radiation) recorded with scattering vector oriented along the long axis of the rod. The data obtained at the chilled end (bottom) show a polycrystalline structure while the center part 5 cm away from the chilled end, which was slowly removed from the hot zone (top), has a strong fiber texture along the  direction. (b) Magnetostriction at room temperature measured with a strain gauge vs. magnetic field oriented along the long axis of the rod.
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f1: Texture and magnetostriction of Tb0.3Dy0.7Fe1.95.(a) X-ray diffraction pattern (Cu Kα radiation) recorded with scattering vector oriented along the long axis of the rod. The data obtained at the chilled end (bottom) show a polycrystalline structure while the center part 5 cm away from the chilled end, which was slowly removed from the hot zone (top), has a strong fiber texture along the direction. (b) Magnetostriction at room temperature measured with a strain gauge vs. magnetic field oriented along the long axis of the rod.

Mentions: A Tb0.3Dy0.7Fe1.95 rod was obtained by employing a modified Bridgman method for crystal growth, see Methods section. Figure 1(a) shows the x-ray diffraction (XRD) pattern of two pieces of material. The data obtained from a piece cut from the chilled end of the rod (bottom) indicate a polycristalline structure, while the piece cut from the part slowly retracted from the hot zone 5 cm from the chilled end (top) has a preferred orientation with the crystallographic axes along the rod axis. The direction makes an angle of 35 degrees with the direction which is the magnetic easy-axis16181920. Pieces cut from this directionally solidified part of the rod were used for the conductance and magnetostriction measurements. The magnetostriction vs. magnetic field H is plotted in Fig. 1(b) which confirms a giant value of λ ≈ 1.5 × 10−3 in 0.4 Tesla at room temperature.


Remote control of magnetostriction-based nanocontacts at room temperature.

Jammalamadaka SN, Kuntz S, Berg O, Kittler W, Kannan UM, Chelvane JA, Sürgers C - Sci Rep (2015)

Texture and magnetostriction of Tb0.3Dy0.7Fe1.95.(a) X-ray diffraction pattern (Cu Kα radiation) recorded with scattering vector oriented along the long axis of the rod. The data obtained at the chilled end (bottom) show a polycrystalline structure while the center part 5 cm away from the chilled end, which was slowly removed from the hot zone (top), has a strong fiber texture along the  direction. (b) Magnetostriction at room temperature measured with a strain gauge vs. magnetic field oriented along the long axis of the rod.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4555029&req=5

f1: Texture and magnetostriction of Tb0.3Dy0.7Fe1.95.(a) X-ray diffraction pattern (Cu Kα radiation) recorded with scattering vector oriented along the long axis of the rod. The data obtained at the chilled end (bottom) show a polycrystalline structure while the center part 5 cm away from the chilled end, which was slowly removed from the hot zone (top), has a strong fiber texture along the direction. (b) Magnetostriction at room temperature measured with a strain gauge vs. magnetic field oriented along the long axis of the rod.
Mentions: A Tb0.3Dy0.7Fe1.95 rod was obtained by employing a modified Bridgman method for crystal growth, see Methods section. Figure 1(a) shows the x-ray diffraction (XRD) pattern of two pieces of material. The data obtained from a piece cut from the chilled end of the rod (bottom) indicate a polycristalline structure, while the piece cut from the part slowly retracted from the hot zone 5 cm from the chilled end (top) has a preferred orientation with the crystallographic axes along the rod axis. The direction makes an angle of 35 degrees with the direction which is the magnetic easy-axis16181920. Pieces cut from this directionally solidified part of the rod were used for the conductance and magnetostriction measurements. The magnetostriction vs. magnetic field H is plotted in Fig. 1(b) which confirms a giant value of λ ≈ 1.5 × 10−3 in 0.4 Tesla at room temperature.

Bottom Line: This can be achieved by exploiting the magnetostriction effects of ferromagnetic materials.Investigating the conductance in the regime of electron tunneling by mechanical or magnetostrictive control of the electrode separation enables an estimation of the magnetostriction.The present results pave the way to utilize the material in devices based on nano-electromechanical systems operating at room temperature.

View Article: PubMed Central - PubMed

Affiliation: Magnetic Materials and Device Physics Laboratory, Department of Physics, Indian Institute of Technology Hyderabad, Hyderabad 502 205, India.

ABSTRACT
The remote control of the electrical conductance through nanosized junctions at room temperature will play an important role in future nano-electromechanical systems and electronic devices. This can be achieved by exploiting the magnetostriction effects of ferromagnetic materials. Here we report on the electrical conductance of magnetic nanocontacts obtained from wires of the giant magnetostrictive compound Tb0.3Dy0.7Fe1.95 as an active element in a mechanically controlled break-junction device. The nanocontacts are reproducibly switched at room temperature between "open" (zero conductance) and "closed" (nonzero conductance) states by variation of a magnetic field applied perpendicularly to the long wire axis. Conductance measurements in a magnetic field oriented parallel to the long wire axis exhibit a different behaviour where the conductance switches between both states only in a limited field range close to the coercive field. Investigating the conductance in the regime of electron tunneling by mechanical or magnetostrictive control of the electrode separation enables an estimation of the magnetostriction. The present results pave the way to utilize the material in devices based on nano-electromechanical systems operating at room temperature.

No MeSH data available.


Related in: MedlinePlus