M. Julliere, Tunneling between ferromagnetic lms, Phys. Lett. A, vol.54, issue.3, pp.225-226, 1975.

T. Miyazaki and N. Tezuka, Giant magnetic tunneling e ect in fe/al2o3/fe junction, J. Magn. Magn. Mater, vol.139, issue.3, pp.231-234, 1995.

A. Brataas, A. D. Kent, and H. Ohno, Current-induced torques in magnetic material, Nat. Mater, vol.11, pp.372-381, 2012.

D. C. Worledge, G. Hu, D. W. Abraham, J. Z. Sun, P. L. Trouilloud et al., Spin torque switching of perpendicular ta|cofeb|mgo-based magnetic tunnel junctions, Appl. Phys. Lett, vol.98, p.22501, 2011.

J. C. Slonczewski, Current-driven excitation of magnetic multilayers, J. Magn. Magn. Mater, vol.159, issue.1-2, pp.1-7, 1996.

L. Berger, Emission of spin waves by a magnetic multilayer traversed by a current, Phys. Rev. B, vol.54, issue.13, 1996.

M. Gajek, J. J. Nowak, J. Z. Sun, P. L. Trouilloud, E. J. O'sullivan et al., Spin torque switching of 20nm magnetic tunnel junctions with perpendicular anisotropy, Appl. Phys. Lett, vol.100, p.132408, 2012.

S. Ikeda, J. Hayakawa, Y. Ashizawa, Y. M. Lee, K. Miura et al., Tunnel magnetoresistance of 604% at 300k by suppression of ta diffusion in cofeb/mgo/cofeb pseudo-spin-valves annealed at high temperature, Appl. Phys. Lett, vol.93, p.82508, 2008.

D. C. Worledge, G. Hu, D. W. Abraham, P. L. Trouilloud, and S. Brown, Development of perpendicularly magnetized ta|cofeb|mgo-based tunnel junctions at ibm, J. Appl. Phys, vol.115, p.172601, 2013.

S. Ikeda, K. Miura, H. Yamamoto, K. Mizunuma, H. D. Gan et al., A perpendicular-anisotropy cofeb-mgo magnetic tunnel junction, Nat. Mater, vol.9, pp.721-724, 2010.

J. J. Nowak, R. P. Robertazzi, J. Z. Sun, G. Hu, D. W. Abraham et al.,

E. J. Gaidis, W. J. O'sullivan, D. C. Gallagher, and . Worledge, Demonstration of ultralow bit error rates for spin-torque magnetic random-access memory with perpendicular magnetic anisotropy, IEEE Magn. Lett, vol.2, issue.3000204, 2011.

J. Z. Sun, S. L. Brown, W. Chen, E. A. Delenia, M. C. Gaidis et al.,

P. Parkin, P. M. Rice, G. Sandhu, T. Topuria, and D. C. Worledge, Spin-torque switching e ciency in cofeb-mgo based tunnel junctions, Phys. Rev. B, vol.88, 2013.

D. C. Ralph and M. Stiles, Spin transfer torques, J. Magn. Magn. Mater, vol.320, pp.1190-1216, 2008.

S. S. Parkin, M. Hayashi, and L. Thomas, Magnetic domain-wall racetrack memory, Science, vol.320, issue.5873, pp.190-194, 2008.

B. Behin-aein, D. Datta, S. Salahuddin, and S. Datta, Proposal for an all-spin logic device with built-in memory, Nat. Nano, vol.5, pp.266-270, 2010.

T. J. Silva and W. H. Rippard, Developments in nano-oscillators based upon spin transfer point-contact devices, J. Magn. Magn. Mater, vol.320, pp.1260-1271, 2008.

K. Kudo, T. Nagasawa, R. Sato, and K. Mizushima, Measurement of nonlinear frequency shift coe cient in spin-torque oscillators based on mgo tunnel junctions, Appl. Phys. Lett, vol.95, p.22507, 2009.

X. Cheng, J. A. Katine, G. E. Rowlands, and I. N. Krivorotov, Nonlinear ferromagnetic resonance induced by spin torque in nanoscale magnetic tunnel junctions, Appl. Phys. Lett, vol.103, p.82402, 2013.

L. Berger, Low-eld magnetoresistance and domain drag in ferromagnets, J. Appl. Phys, vol.49, issue.3, pp.2516-2161, 1978.

M. Yamanouchi, D. Chiba, F. Matsukura, and H. Ohno, Current-induced domain-wall switching in a ferromagnetic semiconductor structure, Nature, vol.428, pp.539-542, 2004.

M. Kläui, Controlled and reproducible domain wall displacement by current pulses injected into ferromagnetic ring structures, Phys. Rev. Lett, vol.94, p.106601, 2005.

N. Vernier, D. A. Allwood, D. Atkinson, M. D. Cooke, and R. P. Cowburn, Domain wall propagation in magnetic nanowires by spin-polarized current injection, Europhys. Lett, vol.65, issue.4, pp.526-532, 2004.
URL : https://hal.archives-ouvertes.fr/hal-00020090

A. Thiaville, Y. Nakatani, J. Miltatand, and Y. Suzuki, Micromagnetic understanding of current-driven domain wall motion in patterned nanowires, Europhys. Lett, vol.69, pp.990-996, 2005.
URL : https://hal.archives-ouvertes.fr/hal-00022918

G. S. Beach, M. Tsoi, and J. L. Erkine, Current-induced domain wall motion, J. Magn. Magn. Mater, vol.320, issue.7, pp.1272-1281, 2008.

J. Lee, Universality classes of magnetic domain wall motion, Phys. Rev. Lett, vol.107, p.67201, 2011.

I. M. Miron, G. Gaudin, S. Au-ret, B. Rodmacq, A. Schuhl et al., Current-driven spin torque induced by the rashba e ect in a ferromagnetic metal layer, Nat. Mater, vol.9, issue.3, pp.230-234, 2010.

A. Ho-mann, Spin hall e ects in metals, IEEE Trans. Magn, vol.49, issue.10, pp.5172-5193, 2013.

J. C. Sanchez, L. Vila, G. Desfonds, S. Gambarelli, J. P. Attane et al., Spin-to-charge conversion using rashba coupling at the interface between non-magnetic materials, Nat. Comm, vol.4, issue.3944, 2013.
URL : https://hal.archives-ouvertes.fr/hal-02042921

K. Lee, S. Lee, B. Min, and K. Lee, Threshold current for switching of a perpendicular magnetic layer induced by spin hall e ect, Appl. Phys. Lett, vol.102, p.112410, 2013.

Y. Lau, D. Betto, K. Rode, J. M. Coey, and P. Stamenov, Spin-orbit torque switching without external eld with a ferromagnetic exchange-biased coupling layer, Nat. Tech, vol.11, pp.758-762, 2016.

A. Van-den, G. Brink, A. Vermijs, J. Solignac, J. T. Koo et al., Field-free magnetization reversal by spin-hall e ect and exchange bias, Nat. Comm, vol.7, 2016.

C. Kittel, Introduction to Solid State Physics, 1996.

A. P. Sutton, Electronic Structure of Materials, 1993.

R. Meservey and P. M. Tedrow, Spin-polarized electron tunneling, Physics Reports, vol.238, issue.4, pp.173-243, 1994.

E. Y. Tsymbal, O. N. Mryasov, and P. R. Leclair, Spin-dependent tunneling in magnetic tunnel junctions, vol.19, 2003.

M. B. Stearns, Simple explanation of tunneling spin-polarization of fe, co, ni and its alloys, J. Magn. Magn. Mater, vol.5, issue.2, pp.167-171, 1977.

J. C. Slonczewski, Conductance and exchange coupling of two ferromagnets separated by a tunneling barrier, Phys. Rev. B, vol.39, issue.10, pp.6995-7002, 1989.

J. Scola, H. Polovy, C. Fermon, M. Pannetier-lecoeur, G. Feng et al., Noise in mgo barrier magnetic tunnel junctions with cofeb electrodes: In uence of annealing temperature, Appl. Phys. Lett, vol.90, 2007.

K. Oguz, P. Jivrajka, M. Venkatesan, G. Feng, and J. M. Coey, Magnetic dead layers in sputtered lms, J. Appl. Phys, vol.103, issue.07B526, 2008.

Y. M. Lee, J. Hayakawa, S. Ikeda, F. Matsukura, and H. Ohno, E ect of electrode composition on the tunnel magnetoresistance of pseudo-spin-valve magnetic tunnel junction with a mgo tunnel barrier, Appl. Phys. Lett, vol.90, 2007.

Z. Diao, D. Apalkov, M. Pakala, Y. Ding, A. Panchula et al., Spin transfer switching and spin polarization in magnetic tunnel junctions with mgo and alox barriers, Appl. Phys. Lett, vol.87, pp.232502-232503, 2005.

Y. Huai, F. Albert, P. Nguyen, M. Pakala, and T. Valet, Observation of spin-transfer switching in deep submicron-sized and lowresistance magnetic tunnel junctions, Appl. Phys. Lett, vol.84, issue.3118, 2004.

K. Yagami, A. A. Tulapurkar, A. Fukushima, and Y. Suzuki, Low-current spin-transfer switching and its thermal durability in a low-saturation magnetization nanomagnets, Appl. Phys. Lett, vol.85, issue.5634, 2004.

W. H. Butler, X. G. Zhang, T. C. Schulthess, and J. M. Maclaren, Spin-dependent tunneling conductance of fe|mgo|fe sandwiches, Phys. Rev. B, vol.63, p.54416, 2001.

J. Mathon and A. Umerski, Theory of tunneling magnetoresistance of an epitaxial fe/mgo/fe(001) junction, Phys. Rev. B, vol.63, 2001.

S. Yuasa, T. Nagahama, A. Fukushima, Y. Suzuki, and K. Ando, Giant room temperature magnetoresistance in single-crystal fe/mgo/fe magnetic tunnel junctions, Nat. Mat, vol.3, pp.868-871, 2004.

S. S. Parkin, Giant tunnelling magnetoresistance at room temperature with mgo (100) tunnel barriers, Nat. Mat, vol.3, pp.862-867, 2004.

R. Shimabukuro, K. Nakamura, T. Akiyama, and T. Ito, Electric eld e ects on magnetocrystalline anisotropy in ferromagnetic fe monolayers, Phys. E, vol.42, issue.4, pp.1014-1017, 2010.

H. X. Yang, M. Chshiev, B. Dieny, J. H. Lee, A. Manchon et al., First-principles investigation of the very large perpendicular magnetic anisotropy at fe|mgo and co|mgo interfaces, Phys. Rev. B, vol.84, issue.054401, 2011.

S. Cardoso, R. Ferreira, P. P. Freitas, M. Mackenzie, J. Chapman et al., Ferromagnetic coupling eld reduction in cofeb tunnel junctions deposited by ion beam, IEEE Trans. Magn, vol.40, issue.4, 2004.

S. Yuasa, T. Nagahama, A. Fukushima, Y. Suzuki, and K. Ando, Giant room-temperature magnetoresistance in single-crystal fe/mgo/fe magnetic tunnel junctions, Nat. Mat, vol.3, pp.868-871, 2004.

K. Tsunekawa, D. D. Djayaprawira, S. Yuasa, M. Nagai, H. Maehara et al., Huge magnetoresistance and low junction resistance in magnetic tunnel junctions with crystalline mgo barrier, IEEE Trans. Magn, vol.42, issue.2, 2006.

L. Ye, C. Lee, J. Syu, Y. Wang, K. Lin et al., E ect of annealing and barrier thickness on mgobasedco/pt and co/pd multilayered perpendicular magnetic tunnel junctions, IEEE Trans. Magn, vol.44, issue.11, 2008.

T. Niizeki, H. Kubota, Y. Ando, and T. Miyazaki, Nanofabrication of magnetic tunnel junctions by using electron beam lithography, J. Magn. Magn. Mat, vol.3, pp.1947-1948

C. Mocuta, A. Barbier, A. V. Ramos, M. Guittet, J. Moussy et al., E ect of optical lithography patterning on the crystalline structure of tunnel junctions, Appl. Phys. Lett, vol.91, 2007.

E. M. Lifshitz-48 and . Landau, Theory of the dispersion of magnetic permeability in ferromagnetic bodies, Phys. Z. Sowietunion, vol.8, pp.153-169, 1935.

T. L. Gilbert, A lagrangian formulation of the gyromagnetic equation of the magnetic eld, Physical Review, vol.100, p.1243, 1955.

J. C. Slonczewski, Currents, torques, and polarization factors in magnetic tunnel junctions, Phys. Rev. B, vol.71, p.24411, 2005.

J. C. Slonczewski, Currents and torques in metallic magnetic multilayers, J. Magn. Magn. Mater, vol.247, pp.324-338, 2002.

Z. Li and S. Zhang, Magnetization dynamics with spin transfer torque, Phys. Rev. B, vol.68, p.24404, 2003.

S. I. Kiselev, J. C. Sankey, I. N. Krivorotov, N. C. Emley, R. J. Schoelkopf et al., Microwave oscillations of a nanomagnet driven by a spin-polarized current, Nature, vol.425, pp.380-383, 2003.

W. H. Rippard, M. R. Pufall, S. Kaka, S. E. Russek, and T. J. Silva, Direct-current induced dynamics in co90fe10/ni80fe20 point contacts, Phys. Rev. Lett, vol.92, p.27201, 2004.

D. Kent, B. Özyilmaz, and E. Del-barco, Spin-transfer-induced precessional magnetization reversal, Appl. Phys. Lett, vol.84, issue.3897, 2004.

H. Liu, D. Bedau, J. Z. Sun, S. Mangin, E. E. Fullerton et al., Dynamics of spin torque switching in all-perpendicular spin valve nanopillars, J. Magn. Magn. Mater, pp.233-258, 2014.
URL : https://hal.archives-ouvertes.fr/hal-01282625

A. Zangwill and M. D. Stiles, Noncollinear spin transfer in co/cu/co multilayers, J. Appl. Phys, vol.91, issue.6812, 2002.

J. Xiao, A. Zangwill, and M. D. Stiles, Boltzmann test of slonczewski's theory of spintransfer torque, Phys. Rev. B, vol.70, 2004.

Y. Huai, F. Albert, P. Nguyen, M. Pakala, and T. Valet, Observation of spin transfer switching in deep submicron-sized and low-resistance magnetic tunnel junctions, Appl. Phys. Lett, vol.84, pp.3118-3120, 2004.

Z. Diao, Spin transfer switching and spin polarization in magnetic tunnel junctions with mgo and alox barriers, Appl. Phys. Lett, vol.87, pp.232502-232503, 2005.

K. Hitoshi, Evaluation of spin-transfer switching in cofeb/mgo/cofeb magnetic tunnel junctions, Jpn. J. Appl. Phys, vol.44, pp.1237-1240, 2005.

H. Jun, Current-driven magnetization switching in cofeb/mgo/cofeb magnetic tunnel junctions, Jpn. J. Appl. Phys, vol.44, pp.1267-1270, 2005.

S. Zhang, P. M. Levy, A. C. Marley, and S. S. Parkin, Quenching of magnetoresistence by hot electrons in magnetic tunnel junctions, Phys. Rev. Lett, vol.79, issue.19, 1997.

K. Carva and I. Turek, Landauer theory of ballistic torkances in non-collinear spin valves, Phys. Rev. B, vol.80, p.104432, 2009.

J. C. Slonczewski and J. Z. Sun, Theory of voltage dirven current and torque in magnetic tunnel junctions, J. Magn. Magn. Mater, vol.310, pp.169-175, 2007.

G. D. Fuchs, J. A. Katine, S. I. Kiselev, D. Mauri, K. S. Wooley et al., Spin torque, tunnel-current spin polarization, and magnetoresistance in mgo magnetic tunnel junctions, Phys. Rev. Lett, vol.96, p.186603, 2006.

J. C. Sankey, Y. Cui, J. Z. Sun, J. C. Slonczewski, R. A. Buhrman et al., Measurement of the spin-transfer-torque vector in magnetic tunnel junctions, Nat. Phys, vol.4, pp.67-71, 2008.

H. Kubota, A. Fukushima, K. Yakushiji, T. Nagahama, S. Yuasa et al., Quantitative measurement of voltage dependence of spin-transfer torque in mgo-based magnetic tunnel junctions, Nat. Phys, vol.4, pp.37-41, 2008.

A. M. Deac, A. Fukushima, H. Kubota, H. Maehara, Y. Suzuki et al., Bias-driven high-power microwave emission from mgo-based tunnel magnetoresistance devices, Nat. Phys, vol.4, pp.803-809, 2008.

S. Oh, S. Park, A. Manchon, M. Chshiev, J. Han et al., Bias-voltage dependence of perpendicular spintransfer torque in asymmetric mgo-based magnetic tunnel junctions, Nat. Phys, vol.5, pp.898-902, 2009.

Y. Tang, N. Kioussis, A. Kalitsov, W. H. Butler, and R. Car, Field-like spin torque in magnetic tunnel junctions, Journal of Physics: Conference Series, p.6203, 2010.

C. Wang, Y. Cui, J. A. Katine, R. A. Buhrman, and D. C. Ralph, Time-resolved measurement of spin-transfer-driven ferromagnetic resonance and spin torque in magnetic tunnel junctions, Nat. Phys, vol.7, pp.496-501, 2011.

T. Min, J. Z. Sun, R. Beach, D. Tang, and P. Wang, Back-hopping after spin torque transfer induced magnetization switching in magnetic tunneling junction cells, J. Appl. Phys, vol.105, pp.7-126, 2009.

J. Z. Sun, M. C. Gaidis, G. Hu, E. J. O'sullivan, S. L. Brown et al., High-bias backhopping in nanosecond time-domain spin-torque switches of mgo-based magnetic tunnel junctions, J. Appl. Phys, vol.105, pp.7-109, 2009.

I. Theodonis, N. Kioussis, A. Kalitsov, M. Chshiev, and W. H. Butler, Anomalous bias dependence of spin torque in magnetic tunnel junctions, Phys. Rev. Lett, vol.97, p.237205, 2006.

J. Xiao, G. W. Bauer, and A. Brataas, Spin-transfer torque in magnetic tunnel junctions: Scattering theory, Phys. Rev. B, vol.77, p.224419, 2008.

C. Wang, Y. Cui, J. Z. Sun, J. A. Katine, R. A. Buhrman et al., Bias and angular dependence of spin-transfer torque in magnetic tunnel junctions, Phys. Rev. B, vol.79, p.224416, 2009.

S. Petit, N. De-mestier, C. Baraduc, C. Thirion, Y. Liu et al., In?uence of spin-transfer torque on thermally activated ferromagnetic resonance excitations in magnetic tunnel junctions, Phys. Rev. B, vol.78, p.184420, 2008.

Z. Wen, H. Sukegawa, S. Kasai, M. Hayashi, S. Mitani et al., Magnetic tunnel junctions with perpendicular anisotropy using a co2feal full-heusler alloy, Appl. Phys. Expr, vol.5, issue.6, 2012.

T. Scheike, H. Sukegawa, T. Furubayashi, Z. Wen, K. Inomata et al., Latticematched magnetic tunnel junctions using a heusler alloy co2feal and a cation-disorder spinel mg-al-o barrier, Appl. Phys. Lett, vol.105, p.242407, 2014.

R. Skomski, J. Zhou, R. D. Kirby, and D. J. Sellmyer, Micromagnetic energy barriers, J. Appl. Phys, vol.99, pp.8-906, 2006.

G. Hu, T. Topuria, P. M. Rice, J. Jordan-sweet, and D. C. Worledge, Optimization of tunneling magnetoresistance in perpendicular magnetic tunnel junctions with co|pd reference layers, IEEE Magn. Lett, vol.4, issue.3000104, 2013.

E. P. Sajitha, J. Walowski, D. Watanabe, S. Mizukami, F. Wu et al., Magnetization dynamics in cofeb bu ered perpendicularly magnetized co/pd multilayer, IEEE Trans. Magn, vol.46, issue.6, 2010.

J. Park, S. Ikeda, H. Yamamoto, H. Gan, K. Mizunuma et al., Perpendicular magnetic tunnel junctions with cofe/pd multilayer electrodes and an mgo barrier, IEEE Trans. Magn, vol.45, issue.10, 2009.

J. W. Knepper and F. Y. Yang, Oscillatory interlayer coupling in co/pt multilayers with perpendicular anisotropy, Phys. Rev. B, vol.71, 2005.

R. Wu, C. Li, and A. J. Freeman, Structural electronic and magnetic properties of co/pd (111) and co/pt (111), J. Magn. Magn. Mater, vol.99, issue.13, pp.71-80, 1991.

D. Weller, Y. Wu, J. Stohr, M. G. Samant, B. D. Hermsmeier et al., Orbital magnetic moment of co in multilayers with perpendicular magnetic anisotropy, Phys. Rev. B, vol.49, pp.12888-12896, 1994.

M. Endo, S. Kanai, S. Ikeda, F. Matsukura, and H. Ohno, Electric eld e ects on thickness dependent magnetic anisotropy of sputtered mgo/co40fe40b20/ta structures, Appl.Phys.Lett, vol.96, p.212503, 2010.

D. C. Worledge, U.s. patent application us, 2010.

N. Miyakawa, D. Worledge, and K. Kita, Impact of ta di usion on the perpendicular magnetic anisotropy of ta/cofeb/mgo, IEEE Magn. Lett, vol.4, 2013.

S. Peng, M. Wang, H. Yang, L. Zeng, J. Nan et al.,

Q. Wang, W. Zhang, and . Zhao, Origin of interfacial perpendicular magnetic anisotropy in mgo/cofe/ metallic capping layer structure, Nat. Sci. Rep, vol.5, p.18173, 2015.

R. Shimabukuro, K. Nakamura, T. Akiyama, and T. Ito, Electric eld e ects on magneto crystalline anisotropy in ferromagnetic fe monolayers, Physica E, vol.42, issue.4, pp.1014-1017, 2010.

J. Z. Sun, R. P. Robertazzi, J. Nowak, P. L. Trouilloud, G. Hu et al., E ect of subvolume excitation and spin-torque e ciency on magnetic switching, Phys. Rev. B, vol.84, issue.064413, 2011.

J. Z. Suna, P. L. Trouilloud, M. J. Gajek, J. Nowak, R. P. Robertazzi et al.,

S. L. Gaidis, E. J. Brown, W. J. O'sullivan, D. C. Gallagher, and . Worledge, Size dependence of spin-torque induced magnetic switching in cofeb-based perpendicular magnetization tunnel junctions, J. Appl. Phys, vol.111, issue.07C711, 2012.

C. You and M. Jung, Dependence of the switching current density on the junction sizes in spin transfer torque, J. Appl. Phys, vol.113, issue.073904, 2013.

K. Bernert, V. Sluka, C. Fowley, J. Lindner, J. Fassbender et al., Phase diagrams of mgo magnetic tunnel junctions including the perpendicular spin-transfer torque in different geometries, Phys. Rev. B, vol.89, 2014.

E. C. Stoner and E. P. Wohlfarth, A mechanism of magnetic hysteresis in heterogeneous alloys, Philosophical Transactions of the Royal Society A: Physical, Mathematical and Engineering Sciences, vol.240, issue.826, 1948.

J. Cucchiara, E. E. Fullerton, A. D. Kent, J. Z. Sun, Y. Henry et al., Current-induced magnetization reversal in terms of power dissipation, Phys. Rev. B, vol.84, p.100405, 2011.
URL : https://hal.archives-ouvertes.fr/hal-01624060

J. Wegrowe and M. Ciornei, Magnetization dynamics, gyromagnetic relation, and inertial e ects, Amer. Jour. Phys, vol.80, issue.607, 2012.

C. Heiliger and M. D. Stiles, Ab initio studies of the spin-transfer torque in magnetic tunnel junctions, Phys. Rev. Lett, vol.100, 2008.

J. M. Shaw, H. T. Nembach, M. Weiler, T. J. Silva, M. Schoen et al., Perpendicular magnetic anisotropy and easy cone state in ta/co fe b /mgo, IEEE Magn. Lett, vol.6, issue.3500404, 2015.

J. Z. Sun, Consequences of an interface-concentrated perpendicular magnetic anisotropy in ultrathin cofeb lms used in magnetic tunnel junctions, Phys. Rev. B, vol.91, 2015.

A. Timopheev, R. Sousa, M. Chshiev, T. Nguyen, and B. Dieny, Second order anisotropy contribution in perpendicular magnetic tunnel junctions, Scienti c Reports, vol.6, 2016.
URL : https://hal.archives-ouvertes.fr/hal-01576674

M. A. Ruderman and C. Kittel, Indirect exchange coupling of nuclear magnetic moments by conduction electrons, Phys. Rev, vol.96, issue.99, 1954.

Y. Yafet, Ruderman-kittel-kasuya-yosida range function of a one-dimensional free-electron gas, Phys. Rev. B, vol.36, issue.3948, 1987.

S. S. Parkin and D. Mauri, Spin engineering: Direct determination of the ruderman-kittelkasuya-yosida far-eld range function in ruthenium, Phys. Rev. B, vol.44, issue.7131, 1991.

L. Néel, Ann. Geophys, vol.5, issue.99, p.1949

W. F. Brown, Thermal uctuations of a single-domain particle, Phys. Rev, vol.130, issue.5, 1963.

W. F. Brown, Thermal uctuation of ne ferromagnetic particles, IEEE Trans. Magn, vol.15, 1197.

H. Suh, C. Heo, C. You, W. Kim, T. Lee et al., Attempt frequency of magnetization in nanomagnets with thin-lm geometry

, Phys. Rev. B, vol.78, issue.064430, 2008.

P. Gaunt, J. Appl. Phys, vol.59, issue.4129, 1986.

R. Dittrich, T. Schre, A. Thiaville, J. Miltat, V. Tsiantos et al., J. Magn. Magn. Mat, issue.747, pp.272-276, 2004.

J. W. Lau, J. K. Bording, M. Beleggia, and Y. Zhu, Energy barrier to magnetic vortex nucleation, Appl. Phys. Lett, vol.88, 2006.

S. Kogan, Electronic Noise and Fluctuations in Solids, 2008.

R. Skomski, J. Zhou, R. D. Kirby, and D. J. Sellmyer, Micromagnetic energy barriers, J. Appl. Phys, vol.99, issue.08B906, 2006.

G. D. Fuchs, I. N. Krivorotov, P. M. Braganca, N. C. Emley, A. G. Garcia et al., Adjustable spin torque in magnetic tunnel junctions with two xed layers

, Appl. Phys. Lett, vol.86, 2005.

G. Grinstein and R. H. Koch, Coarse graining in micromagnetics, Phys. Rev. Lett, vol.90, 2003.

S. Urazhdin, N. O. Birge, W. P. Pratt, and J. Bass, Current-driven magnetic excitations in permalloy-based multilayer nanopillars, Phys. Rev. Lett, vol.94, issue.14, 2003.

Z. Li and S. Zhang, Magnetization dynamics with a spin-transfer torque, Phys. Rev. B, vol.68, 2003.

R. H. Koch, J. A. Katine, and J. Z. Sun, Time-resolved reversal of spin-transfer switching in a nanomagnet, Phys. Rev. Lett, vol.92, issue.088302, 2004.

J. Z. Sun, Spin-current interaction with a monodomain magnetic body: A model study, Phys. Rev. B, vol.62, issue.570, 2000.

S. Petit-watelot, uence du couple de transfert de spin sur les uctuations magnétiques thermiquement activées dans les jonctions tunnel magnétiques. TEl, 2007.

N. Krivorotov, N. C. Emley, A. G. Garcia, J. C. Sankey, S. I. Kiselev et al., Temperature dependence of spin-transfer-induced switching of nanomagnets, Phys. Rev. Lett, vol.93, 2004.

X. Zhu and J. Zhu, Angular dependence of the microwave excitation by direct current, J. Appl. Phys, vol.95, issue.7318, 2004.

R. Dittrich, T. Schre, D. Suess, W. Scholz, H. Forster et al., A path method for nding energy barriers and minimum energy paths in complex micromagnetic systems, J

, Magn. Magn. Mat, vol.250, pp.12-19, 2002.