Publications

Papers and Preprints
Theses

Preprints

2012

Magnetic switching by spin torque from the spin Hall effect.
L. Liu, O. J. Lee, T. J. Gudmundsen, D. C. Ralph, R. A. Buhrman,
Phys. Rev. Lett. 109, 096602 (2012).

Phase locking and frequency doubling in spin-transfer-torque oscillators with two coupled free layers.
T. Moriyama, G. Finocchio, M. Carpentieri, B. Azzerboni, D. C. Ralph, and R. A. Buhrman,
Phys. Rev. B 86, 060411 (2012).

Network Analyzer Measurements of Spin Transfer Torques in Magnetic Tunnel Junctions.
L. Xue, C. Wang, Y.-T. Cui, J. A. Katine, R. A. Buhrman, D. C. Ralph,
Appl. Phys. Lett. 101, 022417 (2012).

Spin torque switching with the giant spin Hall effect of tantalum.
L. Liu, C.-F. Pai, Y. Li, H.-W. Tseng, D. C. Ralph, R. A. Buhrman,
Science 336, 555 (2012) arXiv:1203.2875 (2012)

Resonance measurement of nonlocal spin torque in a 3-terminal magnetic device.
L. Xue, C. Wang, Y.-T. Cui, L. Liu, A. Swander, J. Z. Sun, R. A. Buhrman, D. C. Ralph,
Phys. Rev. Lett. 108, 147201 (2012).

2011

Spin-transfer torque in nanoscale magnetic devices.
D. C. Ralph, Y.-T. Cui, L. Q. Liu, T. Moriyama, C. Wang, and R. A. Buhrman,
Phil. Trans. R. Soc. A 369, 3617 (2011).

Spin-torque-driven ballistic precessional switching with 50 ps impulses.
O. J. Lee, D. C. Ralph, and R. A. Buhrman,
Appl. Phys. Lett. 99, 102507 (2011).

Conditions for microwave amplification due to spin-torque dynamics in magnetic tunnel junctions.
L. Xue, C. Wang, Y.-T. Cui, J. A. Katine, R. A. Buhrman, and D. C. Ralph,
Appl. Phys. Lett. 99, 022505 (2011).

Single-molecule conductance of pyridine-terminated dithienylethene switch molecules.
E. S. Tam, J. J. Parks, W. W. Shum, Y.-W. Zhong, M. B. Santiago-Berrios, X. Zheng, W. Yang, G. K.-L.Chan, H. D. Abruña, and D. C. Ralph,
ACS Nano 5, 5115 (2011) and Supplementary Information.

Correspondence: The electromotive force of MnAs nanoparticles.
D. C. Ralph, Nature 474, E6 (2011).

Time-resolved detection of spin-transfer-driven ferromagnetic resonance and spin torque measurement in magnetic tunnel junctions.
C. Wang, Y.-T. Cui, J. A. Katine, R. A. Buhrman, and D. C. Ralph,
Nature Physics 7, 496 (2011) and Supplementary Information.
(Also see coverage by the Cornell Chronicle.)

Images of a spin-torque-driven magnetic nano-oscillator.
X. W. Yu, V. S. Pribiag, Y. Acremann, A. A. Tulapurkar, T. Tyliszczak, K. W. Chou, B. Bräuer, Z.-P. Li, O. J. Lee, P. G. Gowtham, D. C. Ralph, R. A. Buhrman, and J. Stöhr,
Phys. Rev. Lett. 106, 167202 (2011) and Supplementary Information
Accompanying movies: Video 1, Video 2, and video legends.

Plasmon resonance in individual nanogap electrodes studied using graphene nanoconstrictions as photodetectors.
S.-F. Shi, X. Xu, P. L. McEuen, and D. C. Ralph,
Nano Letters, 11, 1814 (2011).

Electrochemistry of individual monolayer graphene sheets.
W. Li, C. Tan, M. A. Lowe, H. D. Abruña, and D. C. Ralph,
ACS Nano, 5, 2264 (2011).
(Also see coverage by nanotechweb.org.)

Spin torque ferromagnetic resonance induced by the Spin Hall Effect.
L. Q. Liu, T. Moriyama, D. C. Ralph, and R. A. Buhrman,
Phys. Rev. Lett. 106, 036601 (2011).

2010

Tunnel magnetoresistance and spin torque switching in MgO-based magnetic tunnel junctions with a Co/Ni multilayer electrode.
T. Moriyama, T. J. Gudmundsen, P. Y. Huang, L. Q. Liu, D. A. Muller, D. C. Ralph, and R. A. Buhrman,
Appl. Phys. Lett. 97, 072513 (2010).

Mechanical control of spin states in spin-1 molecules and the underscreened Kondo effect.
J. J. Parks, A. R. Champagne, T. A. Costi, W. W. Shum, A. N. Pasupathy, E. Neuscamman, S. Flores-Torres, P. S. Cornaglia, A. A. Aligia, C. A. Balseiro, G. K.-L. Chan, H. D. Abruña, and D. C. Ralph,
Science 328, 1370 (2010) and Supporting Online Material.
(Also see the accompanying Science Perspective and Nature Nanotechnology Highlight, as well as coverage by C&EN, the Cornell Chronicle, NSF, and physicsworld.com.)

Single-shot time-domain studies of spin-torque-driven switching in magnetic tunnel junctions.
Y.-T. Cui, G. Finocchio, C. Wang, J. A. Katine, R. A. Buhrman, and D. C. Ralph,
Phys. Rev. Lett. 104, 097201 (2010).
(Also see the accompanying Physics Viewpoint.)

2009

Long-timescale fluctuations in zero-field magnetic vortex oscillations driven by dc spin-polarized current.
V. S. Pribiag, G. Finocchio, B. J. Williams, D. C. Ralph, and R. A. Buhrman,
Phys. Rev. B 80, 180411(R) (2009).

A new interpretation of electrochemical impedance spectroscopy to measure accurate doping levels for conducting polymers: Separating Faradaic and capacitive currents.
B. Ulgut, J. E. Grose, Y. Kiya, D. C. Ralph, and H. D. Abruña,
Appl. Surf. Sci. 256, 1304 (2009).

Sensitivity of spin-torque diodes for frequency-tunable resonant microwave detection.
C. Wang, Y.-T. Cui, J. Z. Sun, J. A. Katine, R. A. Burhman, and D. C. Ralph,
J. Appl. Phys. 106, 053905 (2009).

Ultrafast switching of a nanomagnet by a combined out-of-plane and in-plane polarized spin-current pulse.
O. J. Lee, V. S. Pribiag, P. M. Braganca, P. G. Gowtham, D. C. Ralph, and R. A. Buhrman, Appl. Phys. Lett. 95, 012506 (2009).

Bias and angular dependence of spin-transfer torque in magnetic tunnel junctions.
C. Wang, Y.-T. Cui, J. Z. Sun, J. A. Katine, R. A. Burhman, and D. C. Ralph,
Phys. Rev. B 79, 224416 (2009).

Quantum confinement and coherence in a two-dimensional electron gas in a carbon-face 3C-SiC/6H-SiC polytype heterostructure.
J. Lu, M. V. S. Chandrashekhar, J. J. Parks, D. C. Ralph, and M. G. Spencer,
Appl. Phys. Lett. 94, 162115 (2009).

Reduction of the spin-torque critical current by partially canceling the free layer demagnetization field.
L. Q. Liu, T. Moriyama, D. C. Ralph, and R. A. Buhrman, Appl. Phys. Lett. 94, 122508 (2009).

A Three-terminal approach to developing spin-torque written magnetic random access memory cells.
P. M. Braganca, J. A. Katine, N. C. Emley, D. Mauri, J. R. Childress, P. M. Rice, E. Delenia, D. C. Ralph, and R. A. Buhrman, IEEE Transactions on Nanotechnology 8, 190 (2009).

2008

Measurement of discrete energy-level spectra in individual chemically-synthesized gold nanoparticles.
F. Kuemmeth, K. I. Bolotin, S.-F. Shi, D. C. Ralph, Nano Lett. 8, 4506 (2008).

Spin-torque-induced rotational dynamics of a magnetic vortex dipole.
G. Finocchio, O. Ozatay, L. Torres, R. A. Buhrman, D. C. Ralph, and B. Azzerboni,
Phys. Rev. B 78, 174408 (2008).

Tunneling spectra of individual magnetic endofullerene molecules.
J. E. Grose, E. S. Tam, C. Timm, M. Scheloske, B. Ulgut, J. J. Parks, H. D. Abruña, W. Harneit, and D. C. Ralph, Nature Materials 7, 884 (2008).

Strong linewidth variation for spin-torque nano-oscillators as a function of in-plane magnetic field angle.
K. V. Thadani, G. Finocchio, Z.-P. Li, O. Ozatay, J. C. Sankey, I. N. Krivorotov, Y.-T. Cui, R. A. Buhrman, and D. C. Ralph, Phys. Rev. B 78, 024409 (2008).

Resonant spin-transfer-driven switching of magnetic devices assisted by microwave current pulses.
Y.-T. Cui, J. C. Sankey, C. Wang, K. V. Thadani, Z.-P. Li, R. A. Buhrman, and D. C. Ralph, Phys. Rev. B 77, 214440 (2008).

Sidewall oxide effects on spin-torque- and magnetic-field-induced reversal characteristics of thin-film nanomagnets.
O. Ozatay, P. G. Gowtham, K. W. Tan, J. C. Read, K. A. Mkhoyan, M. G. Thomas, G. D. Fuchs, P. M. Braganca, E. M. Ryan, K. V. Thadani, J. Silcox, D. C. Ralph, and R. A. Buhrman, Nature Materials 7, 567 (2008) and Supplementary Information.

Enhancement in spin-torque efficiency by nonuniform spin current generated within a tapered nanopillar spin valve.
P. M. Braganca, O. Ozatay, A. G. F. Garcia, O. J. Lee, D. C. Ralph, and R. A. Buhrman, Phys. Rev. B 77, 144423 (2008).

Coupling of Spin and Orbital Motion of Electrons in Carbon Nanotubes.
F. Kuemmeth, S. Ilani, D. C. Ralph, and P. L. McEuen,
Nature 452, 449 (2008) and Supplementary Information.
(Also see the accompanying News & Views, the Nature Physics News & Views. and coverage by the Cornell Chronicle.)

Current Persectives: Spin Transfer Torques.
D. C. Ralph and M. D. Stiles, J. Magn. Magn. Mater. 320, 1190 (2008).
(Updated versions are maintained at arXiv:0711.4608.)

Current Persectives: Magnetoresistance and spin-transfer torque in magnetic tunnel junctions.
J. Z. Sun and D. C. Ralph, J. Magn. Magn. Mater. 320, 1227 (2008).

Time-domain studies of very-large-angle magnetization dynamics excited by spin transfer torques.
I. N. Krivorotov, N. C. Emley, R. A. Buhrman, and D. C. Ralph,
Phys. Rev. B 77, 054440 (2008).

Measurement of the spin-transfer-torque vector in magnetic tunnel junctions.
J. C. Sankey, Y.-T. Cui, J. Z. Sun, J. C. Slonczewski, R. A. Buhrman, and D. C. Ralph, Nature Physics 4, 67 (2008) and Supplementary Information.
(Also see the accompanying News & Views.)

2007

Temperature dependence of anisotropic magnetoresistance and atomic rearrangements in ferromagnetic metal break junctions.
S.-F. Shi, K. I. Bolotin, F. Kuemmeth, and D. C. Ralph, Phys. Rev. B 76, 184438 (2007).

Magnetization reversal driven by spin-polarized current in exchange-biased nanoscale spin valves.
G. Finocchio, I. N. Krivorotov, L. Torres, R. A. Buhrman, D. C. Ralph, and B. Azzerboni, Phys. Rev. B 76, 174408 (2007).

Correspondence: Atomic motion in ferromagnetic break junctions.
S.-F. Shi and D. C. Ralph, Nature Nanotechnology 2, 522 (2007).

Spin-torque ferromagnetic resonance measurements of damping in nanomagnets.
G. D. Fuchs, J. C. Sankey, V. S. Pribiag, L. Qian, P. M. Braganca, A. G. F. Garcia, E. M. Ryan, Z.-P. Li, O. Ozatay, D. C. Ralph, and R. A. Buhrman,
Appl. Phys. Lett. 91, 062507 (2007).

Phonons and conduction in molecular quantum dots: Density functional calculations of Franck-Condon emission rates for bifullerenes in external fields.
C. T. Chang, J. P. Sethna, A. N. Pasupathy, J. Park, D. C. Ralph, and P. L. McEuen,
Phys. Rev. B 76, 045435 (2007).

Tuning the Kondo Effect with a Mechanically Controllable Break Junction.
J. J. Parks, A. R. Champagne, G. R. Hutchison, S. Flores-Torres, H. D. Abruña, and D. C. Ralph, Phys. Rev. Lett. 99, 026601 (2007).
(Also see the Nature Nanotechnology Research Highlight -- pdf.)

Large-amplitude coherent spin waves excited by spin-polarized current in nanoscale spin valves.
I. N. Krivorotov, D. V. Berkov, N. L. Gorn, N. C. Emley, J. C. Sankey, D. C. Ralph, and R. A. Buhrman, Phys. Rev. B 76, 024418 (2007).

Magnetic vortex oscillator driven by d.c. spin-polarized current.
V. S. Pribiag, I. N. Krivorotov, G. D. Fuchs, P. M. Braganca, O. Ozatay, J. C. Sankey, D. C. Ralph, and R. A. Buhrman, Nature Physics 3, 498 (2007).
(Also see the accompanying News & Views.)

Kondo effect in single-molecule spintronic devices.
J. Martinek, L. Bordad, Y. Utsumi, J. König, J. von Delft, D. C. Ralph, G. Schön, and S. Maekawa, J. Magn. Magn. Mater. 310, e343 (2007).

Imaging Electromigration during the Formation of Break Junctions.
T. Taychatanapat, K. I. Bolotin, F. Kuemmeth, and D. C. Ralph, Nano Lett. 7, 652 (2007).
Accompanying movies: Movie 01a, Movie 01b, Movie 02a, Movie 02b, Movie 03, Movie 04, Movie 05, Movie 06.

2006

Anisotropic Magnetoresistance and Anisotropic Tunneling Magnetoresistance due to Quantum Interference in Ferromagnetic Metal Break Junctions.
K. I. Bolotin, F. Kuemmeth, and D. C. Ralph, Phys. Rev. Lett. 97, 127202 (2006).

Signatures of molecular magnetism in single-molecule transport spectroscopy.
M. H. Jo, J. E. Grose, K. Baheti, M. M. Deshmukh, J. J. Sokol, E. M. Rumberger, D. N. Hendrickson, J. R. Long, H. Park, and D. C. Ralph, Nano Lett. 6, 2014 (2006).

Time-Resolved Spin-Torque Switching and Enhanced Damping in Permalloy/Cu/Permalloy Spin-Valve Nanopillars.
N. C. Emley, I. N. Krivorotov, O. Ozatay, A. G. F. Garcia, J. C. Sankey, D. C. Ralph, and R. A. Buhrman, Phys. Rev. Lett. 96, 247204 (2006).

Spin-Transfer-Driven Ferromagnetic Resonance of Individual Nanomagnets.
J. C. Sankey, P. M. Braganca, A. G. F. Garcia, I. N. Krivorotov, R. A. Buhrman, and D. C. Ralph, Phys. Rev. Lett. 96, 227601 (2006) and supporting EPAPS document.
(Also see the accompanying Nature Nanotechnology Research Highlight -- pdf.)

Spin transfer by nonuniform current injection into a nanomagnet.
O. Ozatay, N. C. Emley, P. M. Braganca, A. G. F. Garcia, G. D. Fuchs, I. N. Krivorotov, R. A. Buhrman, and D. C. Ralph, Appl. Phys. Lett. 88, 202502 (2006).

Spin Torque, Tunnel-Current Spin Polarization, and Magnetoresistance in MgO Magnetic Tunnel Junctions.
G. D. Fuchs, J. A. Katine, S. I. Kiselev, D. Mauri, K. S. Wooley, D. C. Ralph, and R. A. Buhrman, Phys. Rev. Lett. 96, 186603 (2006).

Electrochemical properties of self-assembled monolayers of polyaniline: Effects of the thiol substituent and reduced dimensionality.
B. Ulgut, Y. Zhao, J. E. Grose, D. C. Ralph, and H. D. Abruña, Langmuir 22, 4433 (2006).

From ballistic transport to tunneling in electromigrated ferromagnetic breakjunctions.
K. I. Bolotin, F. Kuemmeth, A. N. Pasupathy, and D. C. Ralph, Nano Lett. 6, 123 (2006).

2005

Mechanisms limiting the coherence time of spontaneous magnetic oscillations driven by DC spin-polarized currents.
J. C. Sankey, I. N. Krivorotov, S. I Kiselev, P. M. Braganca, N.C. Emley, R. A. Buhrman, and D. C. Ralph, Phys. Rev. B 72 , 224427 (2005).

Reducing the Critical Current for Short-Pulse Spin-Transfer Switching of Nanomagnets.
P. M. Braganca, I. N. Krivorotov, O. Ozatay, A. G. F. Garcia, N. C. Emley, J. C. Sankey, D. C. Ralph, and R. A. Buhrman, Appl. Phys. Lett. 87, 112507 (2005).

Spin-transfer excitations of permalloy nanopillars for large applied currents.
S. I. Kiselev, J. C. Sankey, I. N. Krivorotov, N.C. Emley, R. A. Buhrman, and D. C. Ralph, Phys. Rev. B 72 , 064430 (2005).

Adjustable spin torque in magnetic tunnel junctions with two fixed layers.
G. D. Fuchs, I. N. Krivorotov, P. M. Braganca, N. C. Emley, A. G. F. Garcia, D. C. Ralph, and R. A. Buhrman, Appl. Phys. Lett. 86, 152509 (2005).

Mechanically-adjustable and electrically-gated single-molecule transistors.
A. R. Champagne, A. N. Pasupathy, and D. C. Ralph, Nano Lett. 5, 305 (2005).

Vibration-assisted electron tunneling in C140 single-molecule transistors.
A. N. Pasupathy, J. Park, C. Chang, A. V. Soldatov, S. Lebedkin, R. C. Bialczak, J. E. Grose, L. A. K. Donev, J. P. Sethna, D. C. Ralph, and Paul. L. McEuen,
Nano Lett. 5, 203 (2005).

Transistor behavior via Au clusters etched from electrodes in an acidic gating solution: Metal nanoparticles mimicking conducting polymers.
J. E. Grose, A. N. Pasupathy, D. C. Ralph, B. Ulgut, and H. D. Abruña,
Phys. Rev. B 71, 035306 (2005).

Time-Domain Measurements of Nanomagnet Dynamics Driven by Spin-Transfer Torques.
I. N. Krivorotov, N. C. Emley, J. C. Sankey, S. I. Kiselev, D. C. Ralph, and R. A. Buhrman,
Science 307, 228 (2005) and Supporting Online Information.
(Also see the accompanying Perspective.)

2004

Temperature dependence of spin-transfer-induced switching of nanomagnets.
I. N. Krivorotov, N. C. Emley, A. G. F. Garcia, J. C. Sankey, S. I. Kiselev, D. C. Ralph and R. A. Buhrman, Phys. Rev. Lett. 93, 166603 (2004).

The Kondo effect in the presence of ferromagnetism.
A. N. Pasupathy, R. C. Bialczak, J. Martinek, J. E. Grose, L. A. K. Donev, P. L. McEuen, and D. C. Ralph, Science 306, 86 (2004)
(Also see the accompanying Perspective.)

Spin-dependent transport in molecular tunnel junctions.
J. R. Petta, S. K. Slater, and D. C. Ralph, Phys. Rev. Lett. 93, 136601 (2004).

Spin-Transfer Effects in Nanoscale Magnetic Tunnel Junctions.
G. D. Fuchs, N. C. Emley, I. N. Krivorotov, P. M. Braganca, E. M. Ryan, S. I. Kiselev, J. C. Sankey, D. C. Ralph, R. A. Buhrman, and J. A. Katine Appl. Phys. Lett. 85, 1205 (2004).

Current-Induced Nanomagnet Dynamics for Magnetic Fields Perpendicular to the Sample Plane. S. I. Kiselev, J. C. Sankey, I. N. Krivorotov, N. C. Emley, M. Rinkoski, C. Perez, R. A. Buhrman, and D. C. Ralph, Phys. Rev. Lett. 93, 036601 (2004).

Reduction of spin transfer by synthetic antiferromagnets.
N. C. Emley, F. J. Albert, E. M. Ryan, I. N. Krivorotov, D. C. Ralph, R. A. Buhrman, J. M. Daughton, and A. Jander, Appl. Phys. Lett. 84, 4257 (2004).

Metal-nanoparticle single-electron transistors fabricated using electromigration.
K. I. Bolotin, F. Kuemmeth, A. N. Pasupathy, and D. C. Ralph,
Appl. Phys. Lett. 84, 3154 (2004).

2003

30 nm Channel Length Pentacene Transistors.
Y. Zhang, J. R. Petta, S. Ambily, Y. Shen, G. G. Malliaras, and D. C. Ralph,
Adv. Mater. 15, 1632 (2003).

Microwave oscillations of a nanomagnet driven by a spin-polarized current.
S. I. Kiselev, J. C. Sankey, I. N. Krivorotov, N. C. Emley, R. J. Schoelkopf, R. A. Buhrman, and D. C. Ralph, Nature 425, 380 (2003).
(Also see the accompanying News & Views.)

Wiring up single molecules.
J. Park, A. N. Pasupathy, J. I. Goldsmith, A. V. Soldatov, C. Chang, Y. Yaish, J. P. Sethna, H. D. Abruña, D. C. Ralph, and P. L. McEuen, Thin Sol. Films 438, 457 (2003).

Nanometer-scale Scanning Sensors Fabricated Using Stencil Lithography.
A. R. Champagne, A. J. Couture, F. Kuemmeth, and D. C. Ralph,
Appl. Phys. Lett. 82, 1111 (2003).

2002

Using single quantum states as spin filters to study spin polarization in ferromagnets.
M. M. Deshmukh and D. C. Ralph, Phys. Rev. Lett. 89, 266803 (2002).

Quantitative study of magnetization reversal by spin-polarized current in magnetic multilayer nanopillars.
F. J. Albert, N. C. Emley, E. B. Myers, D. C. Ralph, and R. A. Buhrman,
Phys. Rev. Lett. 89, 226802 (2002).

Thermally Activated Magnetic Reversal Induced by a Spin-Polarized Current.
E. B. Myers, F. J. Albert, J. C. Sankey, E. Bonet, R. A. Buhrman, and D. C. Ralph,
Phys. Rev. Lett. 89, 196801 (2002).

Measurements of strongly-anisotropic g-factors for spins in single quantum states.
J. R. Petta and D. C. Ralph, Phys. Rev. Lett. 89, 156802 (2002).

Coulomb Blockade and the Kondo Effect in Single Atom Transistors.
J. Park, A. N. Pasupathy, J. I. Goldsmith, C. Chang, Y. Yaish, J. R. Petta, M. Rinkoski, J. P. Sethna, H. D. Abruña, P. L. McEuen, and D. C. Ralph, Nature 417, 722 (2002).
(Also see the accompanying News & Views.)

Equilibrium and Nonequilibrium Electron Tunneling via Discrete Quantum States.
M. M. Deshmukh, E. Bonet, A. N. Pasupathy, and D. C. Ralph,
Phys. Rev. B 65, 073301 (2002).

Solving rate equations for electron tunneling via discrete quantum states.
E. Bonet, M. M. Deshmukh, and D. C. Ralph, Phys. Rev. B 65, 045317 (2002).

2001

Studies of Spin-Orbit Scattering in Noble-Metal Nanoparticles Using Energy Level Tunneling Spectroscopy.
J. R. Petta and D. C. Ralph, Phys. Rev. Lett. 87, 266801 (2001).

Model for Ferromagnetic Nanograins with Discrete Electronic States.
S. Kleff, J. von Delft, M. M. Deshmukh, and D. C. Ralph,
Phys. Rev. B 64, 220401(R) (2001).

Magnetic Anisotropy Variations and Nonequilibrium Tunneling in a Cobalt Nanoparticle.
M. M. Deshmukh, S. Kleff, S. Guéron, E. Bonet, A. N. Pasupathy, J. von Delft, and D. C. Ralph, Phys. Rev. Lett. 87, 226801 (2001).

Spectroscopy of Discrete Energy Levels in Ultrasmall Metallic Grains.
J. von Delft and D. C. Ralph, Physics Reports 345, 61 (2001).

Calculation of Quantum Tunneling for a Spatially Extended Defect: The Dislocation Kink in Copper Has a Low Effective Mass.
T. Vegge, J. P. Sethna, S-A. Cheong, K. W. Jacobsen, C. R. Myers, and D. C. Ralph,
Phys. Rev. Lett. 86, 1546 (2001).

Perspective: A New Twist for Magnets.
D. C. Ralph, Science. 291, 999 (2001) -- pdf.

2000

Measurements of Discrete Electronic States in a Gold Nanoparticle Using Tunnel Junctions Formed from Self-Assembled Monolayers.
J. R. Petta, D. G. Salinas, and D. C. Ralph, Appl. Phys. Lett. 77, 4419 (2000).

Spin-polarized current switching of a Co thin film nanomagnet.
F. J. Albert, J. A. Katine, R. A. Buhrman, and D. C. Ralph,
Appl. Phys. Lett. 77, 3809 (2000).

Role of Spin-Dependent Interface Scattering in Generating Current-Induced Torques in Magnetic Multilayers.
X. Waintal, E. B. Myers, P. W. Brouwer, and D. C. Ralph, Phys. Rev. B 62,12317 (2000).

Point-Contact Studies of Current-Controlled Domain Switching in Magnetic Multilayers.
E. B. Myers, D. C. Ralph, J. A. Katine, F. J. Albert, and R. A. Buhrman,
J. Appl. Phys. 87, 5502 (2000).

Electron Energy Levels in Superconducting and Magnetic Nanoparticles.
D. C. Ralph, S. Guéron, C. T. Black, and M. Tinkham, Physica B 280, 420 (2000).

Current-Driven Magnetization Reversal and Spin Wave Excitations in Co/Cu/Co Pillars.
J. A. Katine, F. J. Albert, R. A. Buhrman, E. B. Myers, and D. C. Ralph,
Phys. Rev. Lett. 84, 3149 (2000).

Tunneling through metallic quantum dots.
M. Tinkham, D. Davidovic, D. C. Ralph, C. T. Black, J. Low Temp. Phys. 118, 271 (2000).

1999

Tunneling via Individual Electronic States in Ferromagnetic Nanoparticles.
S. Guéron, M. M. Deshmukh, E. B. Myers, and D. C. Ralph,
Phys. Rev. Lett. 83, 4148 (1999).

Dephasing in Metals by Two-Level Systems in the 2-Channel-Kondo Regime.
A. Zawadowski, J. von Delft and D. C. Ralph, Phys. Rev. Lett. 83, 2632 (1999).

Nanofabrication Using a Stencil Mask.
M. M. Deshmukh, D. C. Ralph, M. Thomas, and J. Silcox,
Appl. Phys. Lett., 75, 1631 (1999).

Effects of Spin-Orbit Interactions on Tunneling via Discrete Energy Levels in Metal Nanoparticles.
D. G. Salinas, S. Guéron, D. C. Ralph, C. T. Black, and M. Tinkham,
Phys. Rev. B 60, 6137 (1999).

Current-Induced Switching of Domains in Magnetic Multilayer Devices.
E. B. Myers, D. C. Ralph, J. A. Katine, R. N. Louie, and R. A. Buhrman,
Science 285, 867 (1999).

1998 and earlier

The 2-Channel Kondo Model I: Review of Experimental Evidence for its Realization in Metal Nanoconstrictions.
J. von Delft, D. C. Ralph, R. A. Buhrman, A. W. W. Ludwig, and V. Ambegaokar,
Ann. Physics 263, 1 (1998).

Nanolithography with metastable neon atoms: Enhanced rate of contamination resist formation for nanostructure fabrication.
S. J. Rehse, A. D. Glueck, S. A. Lee, A. B. Goulakov, C. S. Menoni, D. C. Ralph, K. S. Johnson and M. Prentiss, Appl. Phys. Lett. 71, 1427 (1997).

Nanostructure fabrication in silicon using cesium to pattern a self-assembled monolayer.
R. Younkin, K. K. Berggren, K. S. Johnson, M. Prentiss, D. C. Ralph, and G. M. Whitesides, Appl. Phys. Lett. 71, 1261 (1997).

Paramagnetic Breakdown of Superconductivity in Ultrasmall Metallic Grains.
F. Braun, J. von Delft, D. C. Ralph, and M. Tinkham, Phys. Rev. Lett. 79, 921 (1997).

Conference Commentary on the Adriatico Research Conference on 'Superconductivity, Andreev Reflection, and Proximity Effect in Mesoscopic Structures'.
D. C. Ralph and V. Ambegaokar, Comments on Condensed Matter Physics 18.

Gate-Voltage Studies of Discrete Electronic States in Aluminum Nanoparticles.
D. C. Ralph, C. T. Black, and M. Tinkham, Phys. Rev. Lett. 78, 4087 (1997).

Ultrasmall Superconductors.
D. C. Ralph, C. T. Black, J. M. Hergenrother, J. G. Lu, and M. Tinkham, in Mesoscopic Electron Transport, page 447, edited by L. L. Sohn, L. P. Kouwenhoven, and G. Schon (Kluwer Academic Publishers, Dordrecht, The Netherlands, 1997).

Chaos, Interactions, and Nonequilibrium Effects in the Tunneling Resonance Spectra of Small Metallic Particles.
O. Agam, N. S. Wingreen, B. L. Altshuler, D. C. Ralph, and M. Tinkham,
Phys. Rev. Lett. 78, 1956 (1997).

Demonstration of a nanolithographic technique using a self-assembled monolayer resist for neutral atomic cesium.
K. K. Berggren, R. Younkin, E. Cheung, M. Prentiss, A. J. Black, G. M. Whitesides, D. C. Ralph, C. T. Black, and M. Tinkham, Adv. Mat. 9, 52 (1997).

Discrete energy levels and superconductivity in nanometer-scale Al particles.
M. Tinkham, D. C. Ralph, C. T. Black, and J. M. Hergenrother, Czech. J. Phys. 46, 3139 Suppl. 6 (1996).

Using Neutral Metastable Argon Atoms and Contamination Lithography to Form Nanostructures in Silicon, Silicon Dioxide, and Gold.
K. S. Johnson, K. K. Berggren, A. Black, C. T. Black, A. P. Chu, N. H. Dekker, D. C. Ralph, J. H. Thywissen, R. Younkin, M. Prentiss, M. Tinkham, and G. M. Whitesides, Appl. Phys. Lett. 69, 2773 (1996).

Nano-particle transistors and energy-level spectroscopy in metals .
D. C. Ralph, C. T. Black, and M. Tinkham, Superlattice Microst. 20, 389 (1996).

Studies of Electron Energy Levels in Single Metal Particles.
D. C. Ralph, C. T. Black, and M. Tinkham, Physica B 218, 258 (1996).

Spectroscopy of the Superconducting Gap in Individual Nanometer-Scale Aluminum Particles.
C. T. Black, D. C. Ralph, and M. Tinkham, Phys. Rev. Lett. 76, 688 (1996).

Spectroscopic Measurements of Discrete Electronic States in Single Metal Particles.
D. C. Ralph, C. T. Black, and M. Tinkham, Phys. Rev. Lett. 74, 3241 (1995).

Photon-Activated Switch Behavior in the Single-Electron Transistor with a Superconducting Island.
J. M. Hergenrother, J. G. Lu, M. T. Tuominen, D. C. Ralph, and M. Tinkham,
Phys. Rev. B 51, 9407(R) (1995).

Kondo Scattering from Atomic Two-Level Tunneling Systems in Metals: Enhanced Conductance, Critical-Bias Transitions, and the Non-Fermi-Liquid Electronic State.
D. C. Ralph and R. A. Buhrman Phys. Rev. B 51, 3554 (1995).

Charge-transport and photon-assisted tunneling in the NSN single-electron transistor.
J. M. Hergenrother, M. T. Tuominen, J. G. Lu, D. C. Ralph and M. Tinkham, Physica B 203, 327 (1994).

Kondo-Assisted and Resonant Tunneling via a Single Charge Trap: A Realization of the Anderson Model Out of Equilibrium.
D. C. Ralph and R. A. Buhrman, Phys. Rev. Lett. 72, 3401 (1994).

Nanoconstriction Microscopy.
R. A. Buhrman and D. C. Ralph in Physics News (1993), supplement to APS News 3, S10 (1994).

2-Channel Kondo Scaling in Conductance Signals from 2-Level Tunneling Systems.
D. C. Ralph, A. W. W. Ludwig, Jan von Delft, and R. A. Buhrman, Phys. Rev. Lett. 72, 1064 (1994). Reply to comment: Phys. Rev. Lett. 75, 770 (1995) and 75, 2786 (1995) (E).

Effects of Electron Heating on Conductance Fluctuations in Mesoscopic Wires.
D. C. Ralph and R. A. Buhrman, Phys. Rev. B 49, 2257(R) (1994).

Impact of a Single Defect on the Conductance: Local Interference and Universal Conductance Fluctuations.
K. S. Ralls, D. C. Ralph, and R. A. Buhrman, Phys. Rev. B 47, 10509 (1993).

Ensemble Studies of Non-linear Conductance Fluctuations in Phase Coherent Samples.
D. C. Ralph, K. S. Ralls, and R. A. Buhrman, Phys. Rev. Lett. 70, 986 (1993).

Observations of Kondo Scattering Without Magnetic Impurities: A Point Contact Study of Two-level Tunneling Systems in Metals.
D. C. Ralph and R. A. Buhrman, Phys. Rev. Lett. 69, 2118 (1992).

Individual Defect Electromigration in Metal Nanobridges.
K. S. Ralls, D. C. Ralph, and R. A. Buhrman, Phys. Rev. B 40, 11561 (1989).

Defect Motion, Electromigration, and Conductance Fluctuations in Metal Nanoconstrictions.
D. C. Ralph, K. S. Ralls, and R. A. Buhrman, in Nanostructure Physics and Fabrication, ed. M. A. Reed and W.P. Kirk, p. 453 (1989).

Theses

Chen Wang, Characterization of spin transfer torque and magnetization manipulation in magnetic nanostructures, August 2012.

Sufei Shi, Electrical and optical study of nanoscale structures, January 2012.

Yongtao Cui, Characterization of magnetic dynamics excited by spin transfer torque in a nanomagnet, August 2011.

Joshua J. Parks, Mechanical control of the Kondo effect and spin states in single molecules, August 2009.

Kiran V. Thadani, Spin-torque-driven microwave frequency dynamics in magnetic nanopillar devices, August 2009.

Ferdinand Kuemmeth, Spin states and spin-orbit coupling in nanostructures, January 2008.

Jacob E. Grose, Electron transport in single-molecule transistors based on high-spin molecules, August 2007.

Jack C. Sankey, Microwave-frequency characterization of spin transfer and individual nanomagnets, August 2007.

Kirill I. Bolotin, Spin-dependent transport in nanoscale structures, January 2007.

Alexandre R. Champagne, Mechanically adjustable single-molecule transistors and stencil mask nanofabrication of high-resolution scanning probes, August 2005.

Abhay N. Pasupathy, Electron transport in molecular transistors, August 2004.

Jason R. Petta, Effects of spin-orbit coupling on single quantum states in metallic quantum dots, May 2003.

Mandar M. Deshmukh, Probing magnetism at the nanometer scale using tunneling spectroscopy, August 2002.

Edward B. Myers, Manipulating nanomagnets with spin-polarized currents, August 2002.

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