Transport in Solids. Peter M Levy. Email: firstname.lastname@example.org Room 625 Meyer Phone:212-998-7737. Material I cover can be found in. General: Solid State Physics, N.W. Ashcroft and N.D. Mermin (Holt, Rinehardt and Winston, 1976) Electronic Transport in Mesoscopic Systems, S. Datta (Cambridge
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Peter M Levy
Room 625 Meyer
Solid State Physics, N.W. Ashcroft and N.D. Mermin (Holt,
Rinehardt and Winston, 1976)
Electronic Transport in Mesoscopic Systems, S. Datta (Cambridge
University Press, 1995).
Transport Phenomena, H. Smith and H.H. Jensen ( Clarendon Press,
J. Rammer and H. Smith, Rev. Mod. Phys. 58, 323 (1986).
Ab-initio theories of electric transport in solid systems with reduced
dimensions, P. Weinberger, Phys. Reports 377, 281-387 (2003).
How we got from 19th century concepts to applications
in computer storage and memories.
1897- The electron is discovered by J.J. Thomson
While each atom scatters electrons, when they form a periodic array the atomic background only electrons from one state k to another with k+K.
This is called Bragg scattering; it is responsible for dividing the continuous energy vs. momentum
curve into bands.
The resistance of metals increases with temperature; that’s sort of intuitive: the greater the thermal agitation the greater the scattering. What was completely unanticipated was the lose of all resistance at a finite temperature.
When mercury was cooled to 4.18K above absolute zero it lost all resistance; once a
current was started one could remove the battery and it would continue to flow as if
there were no collisions any more.
An understanding of this phenomenon was not fully enunciated till 1958 with the theory
of Bardeen-Cooper and Schreiffer. A key ingredient in understanding superconductivity
is the coupling of motion of the background to that of the electrons. While this is largely
responsible for resistance when the two are not coupled, those electrons that are responsible for superconductivity are no longer scattered.
Provides explanation for negligible contribution of conduction electrons to specific heat
The number of carriers depends on temperature; at T=0K there are none.
Lorentz force acting
on trajectory of
A.D. Kent et al
J. Phys. Cond.
Mat. 13, R461
Role of spin-orbit coupling on electron scattering
A.D. Kent et al
J. Phys. Cond.
Mat. 13, R461
Transport properties of dilute alloys, I. Mertig, Rep. Prog. Phys. 62,
Spin Dependent Transport in Magnetic Nanostructures, edited by
S. Maekawa and T. Shinjo ( Taylor and Francis, 2002).
Giant Magnetoresistance in Magnetic Layered and Granular
Materials, by P.M. Levy, in Solid State PhysicsVol. 47,
eds. H. Ehrenreich and D. Turnbull (Academic Press, Cambridge,
MA, 1994) pp. 367-462.
Giant Magnetoresistance in Magnetic Multilayers, by A. Barthélémy,
A.Fert and F. Petroff, Handbook of Ferromagnetic Materials, Vol.12,
ed. K.H.J. Buschow (Elsevier Science, Amsterdam, The Netherlands,
1999) Chap. 1.
Perspectives of Giant Magnetoresistance, by E.Y. Tsymbal and D,G.
Pettifor, in Solid State PhysicsVol. 56, eds. H. Ehrenreich and
F. Spaepen (Academic Press, Cambridge, MA, 2001) pp. 113-237.
M.A.M. Gijs and G.E.W. Bauer, Adv. in Phys. 46, 285 (1997).
J. Bass, W.P. Pratt and P.A. Schroeder, Comments Cond. Mater. Phys.
18, 223 (1998).
J. Bass and W.P. Pratt Jr., J.Mag. Mag. Mater. 200, 274 (1999).
Brataas, G.E.W. Bauer and P. Kelly, Physics Reports 427,
Albert Fert & Peter Grünberg
Two current model in magnetic multilayers
M.N. Baibich et al., Phys. Rev. Lett. 61, 2472 (1988).
DR/R~110% at RT
Field ~10,000 Oe
DR/R~8-17% at RT
Field ~1 Oe
NiFe + Co nanolayer
S.S.P. Parkin et al,
Phys. Rev. Lett. 66, 2152 (1991)
Sputter deposited on MgO(100), MgO(110) and Al2O3 (0001) substrates using Fe/Pt seed layers deposited at 500C and Co/Cu at ~40C
Current perpendicular to the
From IBM website; 1.swf2.swf
Two magnetic metallic electrodes separated by an insulator; transport
controlled by tunneling phenomena not by characteristics of conduction
in metallic electrodes
2000 magnetic tunnel junctions used in magnetic random access memory
From IBM website;
Current-Driven Magnetization Reversal and Spin-Wave Excitations in CoCuCo Pillars
J. A. Katine, F. J. Albert, and R. A. Buhrman
School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853
E. B. Myers and D. C. Ralph
Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853
By spin torques:
Waintal et al-2000
Brataas et al-2000
By current induced interlayer coupling:
currents can be divided in two parts:
Creation of torque on background by the electric current, and
reaction of background to torque.
Latter epitomized by Landau-Lifschitz equation; micromagnetics
Former is current focus article in PRL:
Mechanisms of spin-polarized current-driven magnetization switching
by S. Zhang, P.M. Levy and A. Fert. Phys. Rev. Lett.88, 236601 (2002).
Extension of Valet-Fert to noncollinear multilayers
different length scales
Spin independent transport
Systems (Cambridge Univ. Press, 1995).
Critique of the “mantra” of Landauer’s formula; see M.P. Das
and F. Green, cond-mat/0304573 v1 25Apr 2003.
ballistic, i.e., has a transmission probability T<1 that
The contact resistance is also known as the Sharvin resistance.