Magnetic thin-film insulator with ultra-low spin wave damping for coherent nanomagnonics

Wave control in the solid state has opened new avenues in modern information technology. Surface-acoustic-wave-based devices are found as mass market products in 100 millions of cellular phones. Spin waves (magnons) would offer a boost in today's data handling and security implementations, i.e., image processing and speech recognition. However, nanomagnonic devices realized so far suffer from the relatively short damping length in the metallic ferromagnets amounting to a few 10 micrometers typically. Here we demonstrate that nm-thick YIG films overcome the damping chasm. Using a conventional coplanar waveguide we excite a large series of short-wavelength spin waves (SWs). From the data we estimate a macroscopic of damping length of about 600 micrometers. The intrinsic damping parameter suggests even a record value about 1 mm allowing for magnonics-based nanotechnology with ultra-low damping. In addition, SWs at large wave vector are found to exhibit the non-reciprocal properties relevant for new concepts in nanoscale SW-based logics. We expect our results to provide the basis for coherent data processing with SWs at GHz rates and in large arrays of cellular magnetic arrays, thereby boosting the envisioned image processing and speech recognition.

[1]  Rupert Huber,et al.  Reciprocal Damon-Eshbach-type spin wave excitation in a magnonic crystal due to tunable magnetic symmetry , 2013 .

[2]  V. Kambersky,et al.  Spin-wave relaxation and phenomenological damping in ferromagnetic resonance , 1975 .

[3]  D. T. Edmonds,et al.  Effective Exchange Constant in Yttrium Iron Garnet , 1959 .

[4]  Jun Hu,et al.  Intrinsic spin Seebeck effect in Au/YIG. , 2013, Physical review letters.

[5]  Rupert Huber,et al.  High propagating velocity of spin waves and temperature dependent damping in a CoFeB thin film , 2012 .

[6]  T. Schneider,et al.  Phase reciprocity of spin-wave excitation by a microstrip antenna , 2008 .

[7]  Zbigniew Celinski,et al.  Ferromagnetic resonance linewidth of Fe ultrathin films grown on a bcc Cu substrate , 1991 .

[8]  J. Prieto,et al.  Measurement of the intrinsic damping constant in individual nanodisks of YIG and YIGjPt , 2014, 1402.3630.

[9]  Hidekazu Kurebayashi,et al.  Controlled enhancement of spin-current emission by three-magnon splitting. , 2011, Nature materials.

[10]  Daichi Chiba,et al.  Nonreciprocal emission of spin-wave packet in FeNi film , 2010 .

[11]  Alexander Khitun,et al.  Magnonic Holographic Memory , 2015, IEEE Transactions on Magnetics.

[12]  Mingzhong Wu,et al.  Spin pumping at the magnetic insulator (YIG)/normal metal (Au) interfaces. , 2011, Physical review letters.

[13]  Kang L. Wang,et al.  A Three-Terminal Spin-Wave Device for Logic Applications , 2008, 0810.5589.

[14]  A. Slavin,et al.  Theory of dipole-exchange spin wave spectrum for ferromagnetic films with mixed exchange boundary conditions , 1986 .

[15]  D. Grundler,et al.  Magnonics: Spin Waves on the Nanoscale , 2009 .

[16]  Andrii V. Chumak,et al.  All-linear time reversal by a dynamic artificial crystal , 2010, Nature communications.

[17]  Michael Kabatek,et al.  Damping in yttrium iron garnet nanoscale films capped by platinum. , 2013, Physical review letters.

[18]  Koji Sekiguchi,et al.  Electrical Demonstration of Spin-Wave Logic Operation , 2013 .

[19]  S. Rezende,et al.  Amplification of spin waves by thermal spin-transfer torque. , 2011, Physical review letters.

[20]  Georg Woltersdorf,et al.  Observation of the propagation and interference of spin waves in ferromagnetic thin films , 2008 .

[21]  Georg Friedrich Dürr,et al.  Spin Waves in Nanochannels, Created by Individual and Periodic Bi-component Ferromagnetic Devices , 2012 .

[22]  P. Bortolotti,et al.  Inverse Spin Hall Effect in nanometer-thick YIG/Pt system , 2013 .

[23]  Thomas J. Meitzler,et al.  Conditions for the spin wave nonreciprocity in an array of dipolarly coupled magnetic nanopillars , 2013 .

[24]  B. Leven,et al.  Spin-wave excitation and propagation in microstructured waveguides of yttrium iron garnet/Pt bilayers , 2013, 1311.6305.

[25]  S. Maekawa,et al.  Transmission of electrical signals by spin-wave interconversion in a magnetic insulator , 2010, Nature.

[26]  Mikhail Kostylev,et al.  Excitation of microwaveguide modes by a stripe antenna , 2009 .

[27]  M. Bailleul,et al.  Current-Induced Spin-Wave Doppler Shift , 2008, Science.

[28]  A. Thomas,et al.  Local charge and spin currents in magnetothermal landscapes. , 2011, Physical review letters.

[29]  H Adachi,et al.  Spin Seebeck insulator. , 2010, Nature Materials.

[30]  C. Back,et al.  Anisotropic propagation and damping of spin waves in a nanopatterned antidot lattice. , 2010, Physical review letters.

[31]  Andrew G. Glen,et al.  APPL , 2001 .

[32]  M. Bailleul,et al.  Spin-wave transduction at the submicrometer scale: Experiment and modeling , 2010 .

[33]  G. Melkov,et al.  Magnetization Oscillations and Waves , 1996 .

[34]  J. Prieto,et al.  Measurement of the intrinsic damping constant in individual nanodisks of Y 3 Fe 5 O 12 and Y 3 Fe 5 O 12 | Pt , 2014 .

[35]  Kyung-Jin Lee,et al.  Spin wave nonreciprocity for logic device applications , 2013, Scientific Reports.

[36]  Kang L. Wang,et al.  Magnonic logic circuits , 2010 .

[37]  Tao Liu,et al.  Ferromagnetic resonance of sputtered yttrium iron garnet nanometer films , 2014 .

[38]  Robert E. Marshak,et al.  Isotopic Spin Selection Rules and K 2 0 Decay , 1959 .

[39]  D. Grundler,et al.  Omnidirectional spin-wave nanograting coupler , 2013, Nature Communications.

[40]  T. Schwarze,et al.  Spin Waves in 2D and 3D Magnonic Crystals: From Nanostructured Ferromagnetic Materials to Chiral Helimagnets , 2013 .

[41]  C. S. Tsai,et al.  Spin waves in periodic magnetic structures-magnonic crystals , 2001 .