Magnetoresistance in excess of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mn>200</mml:mn><mml:mi>%</mml:mi></mml:math>in Ballistic Ni Nanocontacts at Room Temperature and 100 Oe

Garcı́a, N.; Muñoz, Manuel; Zhao, Yibing

doi:10.1103/physrevlett.82.2923

Cited by 402 publications

(322 citation statements)

References 23 publications

Supporting

Mentioning

297

Contrasting

Unclassified

Order By: Relevance

“…One of our main results is perhaps the suggested existence of a drastic increase of the GMR with increasing spacer thickness in case of ballistic conductance through a nonmetallic spacer, see section 4 above, where we also suggest an experimental realization along the lines of the 18 recent experiments of Garcia et al, [33].…”

Section: Discussionmentioning

confidence: 69%

“…Within our formalism other situations could also have been treated, e.g. more complicated geometries as (i) the 'constrictions' studied experimentally by Garcia el al., [33], or (ii) quasione-dimensional problems, where the potentials are constant within a layer, but random from one layer to the next. The last-mentioned problem has already been extensively studied by J. Mathon, [17], and in two-dimensional systems by one of the present authors, [42].…”

Section: Discussionmentioning

confidence: 99%

“…The suggested experiment concerning the TMR would therefore be analogous to the very recent set-up of Garcia et al, [33], but with a small semi-conducting tip of the above-mentioned kind.…”

Section: Non-metallic Spacers Cpp Geometrymentioning

confidence: 99%

“…specific magnetic impurities. Such calculations are of course always possible within our formalism, [32,33], and have partially been performed in course of the diploma work of the first one of the present authors; however, as a first step, and since the results with the magnetic impurities were not particularly exciting and have not been documented, also because of lack of space, we keep at present to our simplified description of the impurities. This seems also justified in view of the simplifications made for the band structure and for the geometry of our systems.…”

Section: Impurity Modelsmentioning

confidence: 99%

See 3 more Smart Citations

Systematic two-band model calculations of the GMR effect with metallic and non-metallic spacers and with impurities

Gebele

Böhm

Krey

et al. 2000

Journal of Magnetism and Magnetic Materials

View full text Add to dashboard Cite

By a semi-empirical Green's function method we calculate conductances and the corresponding Giant Magneto-Resistance effects (GMR) of two metallic ferromagnetic films separated by different spacers, metallic and non-metallic ones, in a simplified model on a sc lattice, in CPP and CIP geometries (i.e. current perpendicular or parallel to the planes), without impurities, or with interface-or bulk impurities. The electronic structure of the systems is approximated by two hybridized orbitals per atom, to mimic s-bands and d-bands and their hybridization.We show that such calculations usually give rough estimates only, but of the correct order of magnitude; in particular, the predictions on the impurity effects depend strongly on the model parameters. One of our main results is the prediction of huge CPP-GMR effects for non-metallic spacers in the ballistic limit.

show abstract

Section: Discussionmentioning

confidence: 69%

Section: Discussionmentioning

confidence: 99%

“…The suggested experiment concerning the TMR would therefore be analogous to the very recent set-up of Garcia et al, [33], but with a small semi-conducting tip of the above-mentioned kind.…”

Section: Non-metallic Spacers Cpp Geometrymentioning

confidence: 99%

Section: Impurity Modelsmentioning

confidence: 99%

See 2 more Smart Citations

Systematic two-band model calculations of the GMR effect with metallic and non-metallic spacers and with impurities

Gebele

Böhm

Krey

et al. 2000

Journal of Magnetism and Magnetic Materials

View full text Add to dashboard Cite

show abstract

“…The latter are controlled by external magnetic fields that result in the so called tunnel magnetoresistance [2] (TMR), Giant magnetoresistance [3] (GMR) and Ballistic magnetoresistance [4] (BMR) when the NM layer is a tunnel barrier, a metal and a geometrical nanoconstriction respectively.…”

mentioning

confidence: 99%

Anisotropic magnetoresistance in single electron transport

Fernández-Rossier¹,

Aguado²,

Brey³

2006

Phys. Status Solidi (c)

View full text Add to dashboard Cite

We study the effect of magnetic anisotropy in a single electron transistor with ferromagnetic electrodes and a non-magnetic island. We identify the variation δµ of the chemical potential of the electrodes as a function of the magnetization orientation as a key quantity that permits to tune the electrical properties of the device. Different effects occur depending on the relative size of δµ and the charging energy. We provide preliminary quantitative estimates of δµ using a very simple toy model for the electrodes. In bulk ferromagnets, the dependence of resistance on the angle between the magnetization Ω and the current j gives rise to the so called anisotropic magneto-resistance (AMR). The microscopic origin of this phenomenon is the spin orbit interaction, which also accounts for the stability of the magnetization orientation (magnetic anisotropy). Recently, the concept of Tunneling Anisotropic Magnetoresistance (TAMR) has been proposed theoretically [5] and independently verified in experiments [6,7,8] in tunnel junctions with GaAsMn electrodes. The related concept of Ballistic Anisotropic Magneto Resistance (BAMR) has been proposed theoretically [9] and observed in atomic sized Nickel [10] and Iron nanocontacts [11]. As opposed to TMR and BMR, where the high and low resistance states are related to variations in Ω 1 · Ω 2 , TAMR and BAMR effects occur for Ω 1 = Ω 2 ≡ Ω and depend on the angle between the transport direction and Ω, which is controlled by an external field.The microscopic origin of BAMR and TAMR can be traced back to the dependence of the electronic structure on the angle between Ω and the crystal lattice, originated by the spin orbit (SO) coupling. In ideal 1-dimensional chains, BAMR occurs if the number of bands at the Fermi energy is different for the magnetization parallel and perpendicular to current flow [9]. In real metallic nanocontacts, the transmission of the different channels is not perfect and an ab-initio approach [12] extended to include SO interaction would be necessary to account for the experimental reports. In the case of TAMR the relevant quantity is the transmission [5], which is related to the density of states at the Fermi energy. The size of the AMR effects depends on the relative ratio of the spin orbit interaction ∆ SO , the Fermi energy ǫ F and the exchange splitting J. Not surprisingly, TAMR has been reported first in III-V ferromagnetic semiconductors, where SO coupling is the largest energy scale in the system.Motivated by recent experimental results [13], we consider a different kind of AMR effect, which takes place in a single electron transistor (SET) with ferromagnetic electrodes. Although in the experiments [13] both the electrodes and the dot are made of ferromagnetic GaMnAs, here we consider a simpler SET with

show abstract

Magnetic Properties of Nanoscale Wire and Dot Systems

Mibu

Shigeto

Miyake

et al. 2002

phys. stat. sol. (a)

View full text Add to dashboard Cite

Magnetic nano-wires and nano-dots were fabricated using an electron-beam lithography and liftoff technique, and the magnetic structures were controlled by engineering the size and shape. We demonstrate here the control of magnetic domain formation and domain wall movement in magnetic nano-wires, the measurement of domain wall resistance using nano-contacts between magnetic nano-wires, and the detection of magnetization reversal of the magnetic vortex core in magnetic nano-dots.1. Introduction Nanoscale magnetic systems have been attracting much attention from the fundamental and technical points of view. It is important, for the development of spin technology, to fabricate a variety of magnetic nano-patterns with the size and shape artificially controlled in high accuracy using the latest nano-patterning techniques, and to study magnetic and transport properties from a fundamental viewpoint. In this paper, we demonstrate three examples, where the magnetic structures are controlled by nanoscale patterning. The first is the control of magnetic domain formation and domain wall movement in magnetic nano-wires. It is demonstrated, by applying the giant magnetoresistance (GMR) effect to nano-wires with magnetic/nonmagnetic/magnetic layered structures, that the magnetic switching field of nano-wires can be controlled by attaching a pad at one of the two ends. The second is the measurement of domain wall resistance using nano-contacts between magnetic nano-wires. A magnetic domain wall is confined at a nano-contact and the contribution of the domain wall to the electric resistance is studied. The third is the detection of magnetization reversal of the vortex core in ferromagnetic nano-dots. The switching field of the vortex core in magnetic dots is observed using magnetic force microscopy (MFM). These series studies would lead to a development of new spin technology.

show abstract

Magnetoresistance in excess of200%in Ballistic Ni Nanocontacts at Room Temperature and 100 Oe

Cited by 402 publications

References 23 publications

Systematic two-band model calculations of the GMR effect with metallic and non-metallic spacers and with impurities

Systematic two-band model calculations of the GMR effect with metallic and non-metallic spacers and with impurities

Anisotropic magnetoresistance in single electron transport

Magnetic Properties of Nanoscale Wire and Dot Systems

Contact Info

Product

Resources

About