Thickness-dependent Kapitza resistance in multilayered graphene and other two-dimensional crystals

Ong, Zhun-Yong

doi:10.1103/physrevb.95.155309

Cited by 34 publications

(51 citation statements)

References 45 publications

(104 reference statements)

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“…The TBCs for Gr/SiO 2 and MoS 2 /SiO 2 interfaces are in agreement with previous studies ( 23 , 24 , 29 ). The TBC of the monolayer WSe 2 /SiO 2 interface is lower than for few-layer WSe 2 /SiO 2 ( 30 ), which is not unexpected, because the monolayer has fewer flexural phonon modes available for transmission ( 31 ).…”

Section: Resultsmentioning

confidence: 92%

Ultrahigh thermal isolation across heterogeneously layered two-dimensional materials

et al. 2019

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Heterogeneous integration of nanomaterials has enabled advanced electronics and photonics applications. However, similar progress has been challenging for thermal applications, in part due to shorter wavelengths of heat carriers (phonons) compared to electrons and photons. Here, we demonstrate unusually high thermal isolation across ultrathin heterostructures, achieved by layering atomically thin two-dimensional (2D) materials. We realize artificial stacks of monolayer graphene, MoS2, and WSe2 with thermal resistance greater than 100 times thicker SiO2 and effective thermal conductivity lower than air at room temperature. Using Raman thermometry, we simultaneously identify the thermal resistance between any 2D monolayers in the stack. Ultrahigh thermal isolation is achieved through the mismatch in mass density and phonon density of states between the 2D layers. These thermal metamaterials are an example in the emerging field of phononics and could find applications where ultrathin thermal insulation is desired, in thermal energy harvesting, or for routing heat in ultracompact geometries.

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Section: Resultsmentioning

confidence: 92%

Ultrahigh thermal isolation across heterogeneously layered two-dimensional materials

et al. 2019

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“…The larger TBC of the multilayer MoS2 is due to contribution from additional flexural phonon branches, consistent with previous observations for WSe2 and graphene. 17,23 The effective TBC eventually saturates due to increase in the inter-layer resistance for multi-layer MoS2. We approximate the contribution from the intrinsic TBC in the Supplement Section 5 and notice that this increases with the number of layers, as expected.…”

Section: Tbc Dependence On Number Of 2d Layersmentioning

confidence: 99%

Thermal boundary conductance of two-dimensional MoS2 interfaces

Suryavanshi

Gabourie

Farimani

et al. 2019

Journal of Applied Physics

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Understanding the thermal properties of two-dimensional (2D) materials and devices is essential for thermal management of 2D applications. Here we perform molecular dynamics simulations to evaluate both the specific heat of MoS2 as well as the thermal boundary conductance (TBC) between one to five layers of MoS2 with amorphous SiO2 and between single-layer MoS2 and crystalline AlN. The results of all calculations are compared to existing experimental data. In general, the TBC of such 2D interfaces is low, below ~20 MWm -2 K -1 , due to the weak van der Waals (vdW) coupling and mismatch of phonon density of states (PDOS) between materials. However, the TBC increases with vdW coupling strength, with temperature, and with the number of MoS2 layers (which introduce additional phonon modes). These findings suggest that the TBC of 2D materials is tunable by modulating their interface interaction, the number of layers, and finding a PDOSmatched substrate, with important implications for future energy-efficient 2D electronics, photonics, and thermoelectrics.

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“…Furthermore, trends seen for thickness dependence of TBC [17][18][19]] have yet to be corroborated across exper imental techniques/studies. To address these questions, there have been several efforts to theoretically model thermal transport across a 2D-3D interface by molecular dynamics (MD) [13,[32][33][34][35][36] and various first-principles-based semi-classical (FP-SC) models [11,16,26,[37][38][39][40]. A theoretical model for heat transfer between weakly coupled systems was developed in [37] where the TBC of a Gr/SiO 2 was predicted to be 25 MW • m −2 • K −1 .…”

Section: Introductionmentioning

confidence: 99%

“…Later, MD and FP-SC modeling demonstrated higher TBC values at 15.6 (MD) and 33 MW • m −2 • K −1 (FP-SC) for a Ti/MoS 2 /SiO 2 interface [26]. A multilayer TBC model was recently developed [40] and used to study the thickness dependence of a Gr/ SiO 2 interface. The TBC was predicted to increase from 34.48 to 87.71 MW • m −2 • K −1 from 1 to 14 layers then saturate to the TBC value of graphite/SiO 2 .…”

Section: Introductionmentioning

confidence: 99%

Quantifying thermal boundary conductance of 2D–3D interfaces

Foss

Akšamija

2019

2D Mater.

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Heat dissipation in next-generation electronics based on two-dimensional (2D) materials is a critical issue in their development and implementation. A potential bottleneck for heat removal in 2D-based devices is the thermal pathway from the 2D layer into its supporting substrate. The choice of substrate, its composition and structure, can strongly impact the thermal boundary conductance (TBC). Here we investigate the temperature-dependent TBC of 42 interfaces formed between a group of six 2D materials and seven crystalline and amorphous substrates. We use first-principles density functional perturbation theory to calculate the full phonon dispersion of the 2D layers and substrates and then input them into our model for phonon transport across the 2D-3D interface. Our results show that the TBC depends on the overlap between the vibrational frequencies and can be varied by nearly two orders of magnitude, from as low as ∼0.6 MW • m −2 • K −1 (h-BN on diamond) to ∼40 MW • m −2 • K −1 (h-BN on SiO 2), for the same 2D layer by changing the substrate material. We find that amorphous materials significantly boost the TBC relative to their crystalline counterparts, assuming the two interfaces have the same adhesion, owing to the low-frequency Boson peak feature in their vibrational density of states (vDOS). For crystalline substrates, we further correlate constituent material properties with the calculated TBCs and find that the TBC strongly depends on a combination of the speed of sound, Debye temperature, and density of the substrate as well as the bandwidth of the flexural branch in the 2D material. We conclude that softer substrates with sharp low-frequency features in their vDOS, such as amorphous materials, polymers, and nanoparticles, could have higher TBC, leading to a trade-off between TBC and the thermal conductivity of the substrate.

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Thickness-dependent Kapitza resistance in multilayered graphene and other two-dimensional crystals

Cited by 34 publications

References 45 publications

Ultrahigh thermal isolation across heterogeneously layered two-dimensional materials

Ultrahigh thermal isolation across heterogeneously layered two-dimensional materials

Thermal boundary conductance of two-dimensional MoS2 interfaces

Quantifying thermal boundary conductance of 2D–3D interfaces

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