Thermal conductance of thin film YIG determined using Bayesian statistics

Euler, Christoph; Hołuj, Paulina; Langner, Thomas; Kehlberger, Andreas; Vasyuchka, Vitaliy I.; Kläui, Mathias; Jakob, G.

doi:10.1103/physrevb.92.094406

Cited by 13 publications

(21 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…2(b)), resembling the trend observed for thin film YIG [23]. This is because magnons, the thermal excitation of which is suppressed by applying magnetic field, are scattered by grain boundaries and do not contribute to heat conduction in polycrystalline samples.…”

Section: Resultssupporting

confidence: 57%

Probing length-scale separation of thermal and spin currents by nanostructuring YIG

Miura

Kikkawa

Iguchi

et al. 2017

Phys. Rev. Materials

View full text Add to dashboard Cite

We have fabricated bulk nanostructured ferrimagnetic materials with different grain sizes by sintering ball-milled Y3Fe5O12 (YIG) nanoparticles and measured the grain-size dependence of the thermal conductivity and spin Seebeck thermopower. The nanostructuring reduces both thermal conductivity and thermopower, but the reduction of the latter was found to be considerably stronger despite the moderate difference in magnetization, which suggests that the length scales of transport of magnons and phonons contributing to the spin Seebeck effect are significantly larger than that of phonons carrying thermal current. This is consistent with the measurements of high-magnetic-field response of the spin Seebeck thermopower and lowtemperature thermal conductivity, where the quenching of magnons seen in single-crystalline YIG was not observed in nanostructured YIG due to scattering of long-range low frequency magnons.3

show abstract

Section: Resultssupporting

confidence: 57%

Probing length-scale separation of thermal and spin currents by nanostructuring YIG

Miura

Kikkawa

Iguchi

et al. 2017

Phys. Rev. Materials

View full text Add to dashboard Cite

show abstract

“…We do not find a significant difference in the (perpendicular-to-the-plane) thermal conductivity for a HM/YIG/GGG system for different metals because the thermal transport is limited by the YIG/GGG [29,30]. This means that the thermal gradient across the HM/YIG, which governs the thermally generated spin current, is not significantly impacted by the metal detection layer.…”

Section: Resultsmentioning

confidence: 67%

“…In the YIG bulk material, phonons coexist with magnons and contribute to the thermal conductivity at all temperatures. Our recent measurements of the thermal conductivity as a function of temperature on these YIG samples reveal a minor shift of the peak position of the thermal conductivity with decreasing film thickness [30]. The absence of the pronounced thickness dependence of the thermal conductivity peak in combination with the large mismatch between both peak temperatures suggests a less important contribution of the phonon-magnon interaction than previously assumed for the transverse SSE in YIG.…”

Section: Resultsmentioning

confidence: 77%

Influence of Thickness and Interface on the Low-Temperature Enhancement of the Spin Seebeck Effect in YIG Films

et al. 2016

View full text Add to dashboard Cite

The temperature-dependent longitudinal spin Seebeck effect (LSSE) in heavy metal ðHMÞ=Y 3 Fe 5 O 12 (YIG) hybrid structures is investigated as a function of YIG film thickness, magnetic field strength, and different HM detection materials. The LSSE signal shows a large enhancement with reductions in temperature, leading to a pronounced peak at low temperatures. We find that the LSSE peak temperature strongly depends on the film thickness as well as on the magnetic field. Our result can be well explained in the framework of magnon-driven LSSE by taking into account the temperature-dependent effective propagation length of thermally excited magnons in the bulk of the material. We further demonstrate that the LSSE peak is significantly shifted by changing the interface coupling to an adjacent detection layer, revealing a more complex behavior beyond the currently discussed bulk effect. By direct microscopic imaging of the interface, we correlate the observed temperature dependence with the interface structure between the YIG and the adjacent metal layer. Our results highlight the role of interface effects on the temperature-dependent LSSE in HM/YIG system, suggesting that the temperature-dependent spin current transparency strikingly relies on the interface conditions.

show abstract

“…The measurement of the value of k YIG , as i.e. performed by Euler and coworkers34 for a thin film, is beyond the scopes of this work. Instead, it is possible to represent results from Δ T method together with some possible ranges of results from the heat flux method whose values depend on the range of thermal conductivities k YIG of the YIG film.…”

Section: Resultsmentioning

confidence: 99%

“…As an example of this comparison, we choose a value for k YIG as equal to 8.5 Wm −1 K −1 : this value is obtained at room temperature from films of different thicknesses (6.7 μ m, 2.1 μ m and 190 nm) by Euler and coworkers34. The thermal gradients measured with heat flux method and calculated with k YIG = 8.5 Wm −1 K −1 give values of S LSSE coefficient equal to S LSSE = (9.379 ± 0.062) × 10 −7 V/K and (9.705 ± 0.053) × 10 −7 V/K for Bielefeld University and INRIM, respectively.…”

Section: Resultsmentioning

confidence: 99%

Longitudinal spin Seebeck coefficient: heat flux vs. temperature difference method

Sola

Bougiatioti

Kuepferling

et al. 2017

Sci Rep

View full text Add to dashboard Cite

The determination of the longitudinal spin Seebeck effect (LSSE) coefficient is currently plagued by a large uncertainty due to the poor reproducibility of the experimental conditions used in its measurement. In this work we present a detailed analysis of two different methods used for the determination of the LSSE coefficient. We have performed LSSE experiments in different laboratories, by using different setups and employing both the temperature difference method and the heat flux method. We found that the lack of reproducibility can be mainly attributed to the thermal contact resistance between the sample and the thermal baths which generate the temperature gradient. Due to the variation of the thermal resistance, we found that the scaling of the LSSE voltage to the heat flux through the sample rather than to the temperature difference across the sample greatly reduces the uncertainty. The characteristics of a single YIG/Pt LSSE device obtained with two different setups was (1.143 ± 0.007) 10−7 Vm/W and (1.101 ± 0.015) 10−7 Vm/W with the heat flux method and (2.313 ± 0.017) 10−7 V/K and (4.956 ± 0.005) 10−7 V/K with the temperature difference method. This shows that systematic errors can be considerably reduced with the heat flux method.

show abstract

Thermal conductance of thin film YIG determined using Bayesian statistics

Cited by 13 publications

References 33 publications

Probing length-scale separation of thermal and spin currents by nanostructuring YIG

Probing length-scale separation of thermal and spin currents by nanostructuring YIG

Influence of Thickness and Interface on the Low-Temperature Enhancement of the Spin Seebeck Effect in YIG Films

Longitudinal spin Seebeck coefficient: heat flux vs. temperature difference method

Contact Info

Product

Resources

About