Spin dynamics and manipulation in GaMnAs alloys

We review recent experiments on spin excitation and manipulation in the ferromagnetic semiconductor GaMnAs. Spin dynamics in GaMnAs have been studied by two complementary approaches - by frequency-domain techniques, such as Brillouin light scattering (BLS) and ferromagnetic resonance (FMR); and by optical real-time techniques, such as ultrafast pump-probe magneto-optical spectroscopy. Using BLS and FMR, magnon frequencies (or resonance fields), were investigated as a function of Mn concentration, temperature and direction of magnetization, leading to information on magnetic anisotropy. Time-resolved magneto-optical Kerr effect, on the other hand, was used to study photo-induced femtosecond magnetization rotation, ultrafast optical demagnetization, and collective magnetization precession. Optically-induced transient changes in magnetization of GaMnAs produced by femtosecond laser pulses are analyzed and discussed in terms of the Landau-Lifshitz-Gilbert model. Finally, for completeness, we also discuss carrier-mediated nonthermal and thermal (lattice-heating) contributions to spin dynamics.

[1]  H. Ohno,et al.  An extensive comparison of anisotropies in MBE grown (Ga,Mn)As material , 2008, 0802.4206.

[2]  Magnetization relaxation in (Ga,Mn)As ferromagnetic semiconductors , 2003, cond-mat/0308386.

[3]  X. Liu,et al.  Angular dependence of spin-wave resonances and surface spin pinning in ferromagnetic (Ga,Mn) As films , 2007 .

[4]  A. Oiwa,et al.  Dynamics of photoinduced magnetization rotation in ferromagnetic semiconductor p -(Ga,Mn)As , 2004 .

[5]  T. Dietl,et al.  Magnetic domains in III-V magnetic semiconductors , 2001, cond-mat/0107009.

[6]  X. Liu,et al.  Ultrafast enhancement of ferromagnetism via photoexcited holes in GaMnAs. , 2007, Physical review letters.

[7]  X. Liu,et al.  Ultrafast optical control of coercivity in GaMnAs , 2008 .

[8]  L. Lagae,et al.  All-optical probe of coherent spin waves. , 2002, Physical review letters.

[9]  D. Awschalom,et al.  Semiconductor spintronics and quantum computation , 2002 .

[10]  Carlo Piermarocchi,et al.  Femtosecond coherent control of spins in (Ga,Mn)As ferromagnetic semiconductors using light. , 2009, Physical review letters.

[11]  D. Chow,et al.  Subpicosecond spin relaxation in GaAsSb multiple quantum wells , 1999 .

[12]  Kohlhepp,et al.  Ultrafast magneto-optics in nickel: magnetism or optics? , 2000, Physical review letters.

[13]  W. Ossau,et al.  Picosecond dynamics of the photoinduced spin polarization in epitaxial (Ga,Mn)as films. , 2004, Physical review letters.

[14]  X. Liu,et al.  Determination of free hole concentration in ferromagnetic Ga1−xMnxAs using electrochemical capacitance–voltage profiling , 2002 .

[15]  Tomasz Wojtowicz,et al.  Effect of the location of Mn sites in ferromagnetic GaMnAs on its Curie temperature , 2002 .

[16]  Michael R. Melloch,et al.  The role of point defects and arsenic precipitates in carrier trapping and recombination in low‐temperature grown GaAs , 1996 .

[17]  Light-induced magnetic precession in (Ga,Mn)As slabs : Hybrid standing-wave Damon-Eshbach modes , 2006, cond-mat/0609646.

[18]  A. Oiwa,et al.  Magnetic anisotropy switching in(Ga,Mn)Aswith increasing hole concentration , 2006 .

[19]  Lev Davidovich Landau,et al.  ON THE THEORY OF THE DISPERSION OF MAGNETIC PERMEABILITY IN FERROMAGNETIC BODIES , 1935 .

[20]  Kimberley C. Hall,et al.  Performance of a spin-based insulated gate field effect transistor , 2006 .

[21]  J. Schliemann,et al.  Nonballistic spin-field-effect transistor. , 2002, Physical review letters.

[22]  H. Puszkarski.  Theory of surface states in spin wave resonance , 1979 .

[23]  X. Liu,et al.  Domain Structure and Magnetic Anisotropy in Ga1-xMnxAs , 2004 .

[24]  K. Onodera,et al.  980 nm compact optical isolators using Cd1-x-yMnxHgyTe single crystals for high power pumping laser diodes , 1994 .

[25]  Maksymowicz.  Spin-wave spectra of insulating films: Comparison of exact calculations and a single-wave-vector model. , 1986, Physical review. B, Condensed matter.

[26]  Effect of annealing on the depth profile of hole concentration in (Ga,Mn)As , 2005, cond-mat/0503595.

[27]  G. J. Parker,et al.  Time-resolved measurement of propagating spin waves in ferromagnetic thin films. , 2002, Physical review letters.

[28]  Xiaofeng Liu,et al.  Ferromagnetic resonance in Ga 1 − x Mn x As : Effects of magnetic anisotropy , 2003 .

[29]  I. E. Perakis,et al.  Coherent magnetization precession in GaMnAs induced by ultrafast optical excitation , 2007 .

[30]  Stuart A. Wolf,et al.  Spintronics : A Spin-Based Electronics Vision for the Future , 2009 .

[31]  S. Datta,et al.  Electronic analog of the electro‐optic modulator , 1990 .

[32]  G. Rado,et al.  Spin-wave resonance in a ferromagnetic metal , 1959 .

[33]  T. Jungwirth,et al.  Theory of ferromagnetic (III, Mn) V semiconductors , 2006, cond-mat/0603380.

[34]  Norman H. Tolk,et al.  Ultrafast laser-induced coherent spin dynamics in ferromagnetic Ga 1-x Mn x As/GaAs structures , 2009 .

[35]  All‐optical picosecond switching of a quantum well etalon using spin‐polarization relaxation , 1995 .

[36]  M. Brandt,et al.  Spin-wave resonances and surface spin pinning in Ga 1-x Mn x As thin films , 2009 .

[37]  T. Jungwirth,et al.  Theory of magnetic anisotropy in III 1 − x Mn x V ferromagnets , 2001 .

[38]  D. D. Awschalom,et al.  Highly enhanced Curie temperature in low-temperature annealed [Ga,Mn]As epilayers , 2002 .

[39]  A. MacDonald,et al.  Ferromagnetic semiconductors: moving beyond (Ga,Mn)As , 2005, cond-mat/0503185.

[40]  L. Cywinski,et al.  Ultrafast demagnetization in the sp-d model: A theoretical study , 2007, cond-mat/0703049.

[41]  R. Turk,et al.  Exchange-dominated surface spin waves in thin yttrium-iron-garent films , 1975 .

[42]  M. Oestreich,et al.  Laser threshold reduction in a spintronic device , 2003, Conference on Lasers and Electro-Optics, 2004. (CLEO)..

[43]  J. Furdyna,et al.  Ferromagnetic resonance in Ga1−xMnxAs dilute magnetic semiconductors , 2006 .

[44]  H. Ohno,et al.  Observation of magnetic domain structure in a ferromagnetic semiconductor (Ga, Mn)As with a scanning Hall probe microscope , 2000 .

[45]  H. Ohno,et al.  Transport properties and origin of ferromagnetism in (Ga,Mn)As , 1998 .

[46]  Merle,et al.  Ultrafast spin dynamics in ferromagnetic nickel. , 1996, Physical review letters.

[47]  J. Philipp,et al.  Spin wave resonance in Ga1−xMnxAs , 2003 .

[48]  H. Ohno,et al.  Hole-mediated ferromagnetism in tetrahedrally coordinated semiconductors , 2000, cond-mat/0007190.

[49]  Christopher J. Stanton,et al.  Ultrafast magneto-optics in ferromagnetic III–V semiconductors , 2005 .

[50]  J. Furdyna,et al.  Spatially resolved inhomogeneous ferromagnetism in (Ga,Mn)as diluted magnetic semiconductors: a microscopic study by muon spin relaxation. , 2008, Physical review letters.

[51]  M. Farle.  Ferromagnetic resonance of ultrathin metallic layers , 1998 .

[52]  Y. Hashimoto,et al.  Photoinduced precession of magnetization in ferromagnetic (Ga,Mn)As. , 2007, Physical review letters.

[53]  X. Liu,et al.  Weak localization in Ga1-xMnxAS Evidence of impurity band transport , 2007, 0707.2416.

[54]  Perpendicular magnetization reversal, magnetic anisotropy, multistep spin switching, and domain nucleation and expansion in Ga1−xMnxAs films , 2005, cond-mat/0505322.

[55]  S. Sarma,et al.  Spintronics: Fundamentals and applications , 2004, cond-mat/0405528.

[56]  R. Damon,et al.  Magnetostatic Modes of a Ferromagnetic Slab , 1960 .

[57]  Ilias E. Perakis,et al.  Memory effects in photoinduced femtosecond magnetization rotation in ferromagnetic GaMnAs , 2009 .

[58]  R. Pisarev,et al.  Ultrafast non-thermal control of magnetization by instantaneous photomagnetic pulses , 2005, Nature.