Low-relaxation spin waves in laser-molecular-beam epitaxy grown nanosized yttrium iron garnet films

Lutsev, L. V.; Korovin, A. M.; Bursian, V. E.; Gastev, S. V.; Fedorov, Vladimir V.; Suturin, S. M.; Sokolov, N. S.

doi:10.1063/1.4948304

Cited by 28 publications

(27 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The value of d can be extracted from the period of the fringes, yielding 93, 104, and 115 nm for the YIG thickness on GGG, SGGG, and NGG, and 5.19 ± 0.3, 5.07 ± 0.3, and 5.13 ± 0.6 g cm −3 for the YIG density, respectively. The roughness R a was well below 1 nm, i.e., much smaller than the lattice parameter, but could potentially be further improved by high-temperature annealing before film deposition, as proposed by Lutsev et al [34] The as-grown YIG films are therefore epitaxially strained to match the in-plane lattice parameter of the substrate and have smooth surfaces. [33] Figure 1e shows topographic AFM images of each film.…”

Section: Wwwadvelectronicmatdementioning

confidence: 97%

“…[14,[37][38][39][40][41] The higher value for SGGG/YIG is evidently not a roughness effect since its roughness was similar to that of other samples. [14,34,43] This may arise from magnetic inhomogeneity [34] or the effect of strain and would be improved by the recrystallization of YIG using a post annealing process. [42] In addition, damping parameters were determined independently using the FV SW attenuation length.…”

Section: Damping Parameter Estimationmentioning

confidence: 99%

See 1 more Smart Citation

Static and Dynamic Magnetic Properties of Single‐Crystalline Yttrium Iron Garnet Films Epitaxially Grown on Three Garnet Substrates

Yoshimoto

Goto

Shimada

et al. 2018

Adv Elect Materials

View full text Add to dashboard Cite

sections. Yttrium iron garnet (YIG) is extensively used for SW devices [11][12][13] because of its low intrinsic Gilbert damping, [14][15][16][17][18][19] but other materials with low Gilbert damping have been proposed, including Permalloy [20,21] and Heusler alloys. [22] However, films of low anisotropy materials such as YIG and Permalloy are typically magnetized in plane due to the dominant shape anisotropy and require a substantial external outof-plane magnetic field to saturate the film. This motivates the search for a magnetic material with a low Gilbert damping and a low out-of-plane saturation field, or ideally with a perpendicular magnetic anisotropy (PMA) that promotes an out-of-plane remanent magnetization, in order to realize integrated FV SW devices.The net magnetic anisotropy includes contributions from magnetocrystalline anisotropy, magnetoelastic anisotropy, and shape anisotropy. [9] In epitaxial films, magnetoelastic anisotropy can be tuned via the lattice mismatch with the substrate. Although YIG has only a modest magnetostriction, PMA was reported for 20 nm thick epitaxial YIG on a Sm 3 Ga 5 O 12 (SmGG) buffer layer on a rare-earth-substituted gadolinium gallium garnet (SGGG) substrate and for SGGG/SmGG/40 nm thick YIG/SmGG, [23] in which the top SmGG suppresses strain relaxation. The top SmGG was essential to obtain PMA in >40 nm thick YIG, but such overlayers lead to spacing loss which would decrease the efficiency of SW excitations using an antenna. Seed and buffer layers also lead to a more complex growth and patterning process. PMA has also been obtained in several single-layer rare-earth-substituted garnet films as a result of magnetoelastic anisotropy, [24][25][26][27] but the substitution of rare earth ions for Y in the iron garnet system tends to increase the Gilbert damping. [28,29] In these reports, there were no detailed discussions of the relation between the magnetoelastic anisotropy and the propagation properties of FV SWs.In this work, the effect of epitaxial mismatch on the net anisotropy and damping of YIG is described. By changing the magnetoelastic anisotropy, the field required for saturating the YIG out of plane can be reduced, facilitating the development of FV SW devices. Three epitaxial YIG films were prepared on gadolinium gallium garnet (GGG), SGGG, and neodymium gallium garnet (NGG) substrates directly (without any buffer layers). These substrates have the same crystalline structure but different lattice constants, yielding different lattice strain and Single-crystalline yttrium iron garnet (YIG) films are grown on gadolinium gallium garnet (GGG), rare-earth-substituted GGG, and neodymium gallium garnet (NGG) substrates, and their crystalline structures, surface morphologies, magnetic and magneto-optical properties, spin wave (SW) spectra of the forward volume (FV) mode, and damping parameters are characterized. YIG grown on NGG shows the smallest out-of-plane effective anisotropy field of 1080 Oe among the three samples because of its larger magnetoelastic anisotropy...

show abstract

Section: Wwwadvelectronicmatdementioning

confidence: 97%

Section: Damping Parameter Estimationmentioning

confidence: 99%

Static and Dynamic Magnetic Properties of Single‐Crystalline Yttrium Iron Garnet Films Epitaxially Grown on Three Garnet Substrates

Yoshimoto

Goto

Shimada

et al. 2018

Adv Elect Materials

View full text Add to dashboard Cite

show abstract

“…The smallest wavelength λ that we excited by the conventional CPWs amounted to 310 nm. This value is smaller than the wavelengths so far excited via microwave antenna in thin YIG with thicknesses ranging from 20 to 500 nm 3,6,16 . At the same time, we observe modes of higher order compared to earlier publications reporting spin-wave excitation in thin YIG 3,16,21 and thin ferromagnetic metals 22,23 using bare CPWs.…”

mentioning

confidence: 75%

“…The extracted decay length l d amounted to 0.86 mm. Small λ, high v g and large l d are key figures of merit when aiming at non-charged based signal transmission and logic devices with spin waves.Thin films of the insulating ferrimagnet yttrium iron garnet (YIG) have recently shown to exhibit small spin-wave (SW) damping [1][2][3][4][5][6][7] . A large decay length of up to 0.58 mm was reported for SWs in a 20 nm thick YIG film 3 .…”

mentioning

confidence: 99%

Spin waves with large decay length and few 100 nm wavelengths in thin yttrium iron garnet grown at the wafer scale

Maendl

Stasinopoulos

Grundler

2017

Applied Physics Letters

View full text Add to dashboard Cite

Using conventional coplanar waveguides (CPWs) we excited spin waves with a wavelength λ down to 310 nm in a 200 nm thin yttrium iron garnet film grown by liquid phase epitaxy. Spin-wave transmission was detected between CPWs that we separated by up to 2 mm. For magnetostatic surface spin waves we found a large nonreciprocity of 0.9 and a high group velocity v g of up to 5.4 km/s. The extracted decay length l d amounted to 0.86 mm. Small λ, high v g and large l d are key figures of merit when aiming at non-charged based signal transmission and logic devices with spin waves.Thin films of the insulating ferrimagnet yttrium iron garnet (YIG) have recently shown to exhibit small spin-wave (SW) damping [1][2][3][4][5][6][7] . A large decay length of up to 0.58 mm was reported for SWs in a 20 nm thick YIG film 3 . In Ref.3 , the films were grown by pulsed laser deposition (PLD) on small substrates of (111) gadolinium gallium garnet (GGG) with a lateral size of about 10 mm × 10 mm. Small damping is important for coherent nanomagnonics, low power consumption and devices such as magnonic holography memory, non-linear cellular networks and SW interferometers 3,[8][9][10][11] . Nonreciprocal characteristics of spin waves further enriches possible logic applications 12 . To scale substrate sizes up, PLD is however very challenging. Here, for instance, magnetron sputtering 13 and liquid phase epitaxy 7,14 are more suitable. Still, for decades, commercially available YIG films grown by liquid phase epitaxy (LPE) had a thickness of 1 µm and beyond 15 . Such thicknesses do not allow for application in nanomagnonics. Recently, a 500 nm thick LPE-grown film was explored with and without nanopatterning 16 . Parameters such as decay length l d , group velocity v g , and nonreciprocity parameter β were however not provided. Note that wafer bonding has already been explored to transfer LPE-grown YIG onto Si substrates to advance integrated photonics 17,18 . Such a route might be interesting for hybrid magnonic devices, and it is timely to explore in detail SW properties of thin YIG grown by LPE.We report on experiments performed on a commercially available YIG film ordered with a thickness t = 200 nm that was grown by LPE on a 3" GGG substrate 20 . Using coplanar waveguides (CPWs) we explored spin-wave propagation over broad frequency and magnetic field regimes. The smallest wavelength λ that we excited by the conventional CPWs amounted to 310 nm. This value is smaller than the wavelengths so far excited via microwave antenna in thin YIG with thicknesses ranging from 20 to 500 nm 3,6,16 . At the same time, we observe modes of higher order compared to earlier publications reporting spin-wave excitation in thin YIG 3,16,21 and thin ferromagnetic metals 22,23 using bare CPWs. The nonreciprocity is found to be pronounced with a parameter β of up to 0.9, much larger compared to 20 nm thick YIG 3 . For magnetostatic surface spin waves (MSSWs) we extract a decay length of 0.86 mm that is a factor of 1.5 larger compared to Ref. [3]. The resul...

show abstract

“…This research has been restricted, however, to bends composed of metallic films, such as Permalloy. Insulating magnetic materials, such as yttrium iron garnet (YIG), possess significantly smaller magnetic damping compared to magnetic metals, and it has been recently demonstrated that this small damping persists even when the thickness of YIG is reduced to tens of nanometers [23,24]. This suggests a possibility of using irregular YIG magnonic waveguides within all-magnonic insulator-based technology.…”

mentioning

confidence: 99%

Spin wave propagation in a uniformly biased curved magnonic waveguide

et al. 2017

View full text Add to dashboard Cite

Using Brillouin light scattering microscopy and micromagnetic simulations, we study the propagation and transformation of magnetostatic spin waves across uniformly biased curved magnonic waveguides. Our results demonstrate that the spin wave transmission through the bend can be enhanced or weakened by modifying the distribution of the inhomogeneous internal magnetic field spanning the structure. Our results open up the possibility of optimally molding the flow of spin waves across networks of magnonic waveguides, thereby representing a step forward in the design and construction of the more complex magnonic circuitry.

show abstract

Low-relaxation spin waves in laser-molecular-beam epitaxy grown nanosized yttrium iron garnet films

Cited by 28 publications

References 23 publications

Static and Dynamic Magnetic Properties of Single‐Crystalline Yttrium Iron Garnet Films Epitaxially Grown on Three Garnet Substrates

Static and Dynamic Magnetic Properties of Single‐Crystalline Yttrium Iron Garnet Films Epitaxially Grown on Three Garnet Substrates

Spin waves with large decay length and few 100 nm wavelengths in thin yttrium iron garnet grown at the wafer scale

Spin wave propagation in a uniformly biased curved magnonic waveguide

Contact Info

Product

Resources

About