Kondo-like phonon scattering in thermoelectric clathrates

  title={Kondo-like phonon scattering in thermoelectric clathrates},
  author={Matthias Ikeda and Holger Euchner and X. D. Yan and Petr Tome{\vs} and Andrey Prokofiev and L. Prochaska and G{\"u}nther Lientschnig and Robert Svagera and Stefanie Hartmann and Elena Gati and Michael Lang and Silke Paschen},
  journal={Nature Communications},
Crystalline solids are generally known as excellent heat conductors, amorphous materials or glasses as thermal insulators. It has thus come as a surprise that certain crystal structures defy this paradigm. A prominent example are type-I clathrates and other materials with guest-host structures. They sustain low-energy Einstein-like modes in their phonon spectra, but are also prone to various types of disorder and phonon-electron scattering and thus the mechanism responsible for their ultralow… 

Impact of temperature and mode polarization on the acoustic phonon range in complex crystalline phases: A case study on intermetallic clathrates

The low and weakly temperature-varying lattice thermal conductivity, κL(T), in crystals with a complex unit cell such as type-I clathrates is assumed to originate from a reduced momentum and energy

Anisotropic low-energy vibrational modes as an effect of cage geometry in the binary barium silicon clathrate Ba24Si100

The low lattice thermal conductivity in inorganic clathrates has been shown recently to be related to the low-energy range of optical phonons dominated by motions of guest atoms trapped in a network

Vibrational dynamics of the type-I clathrates A8Sn44□2 (A = Cs, Rb, K) from lattice-dynamics calculations, inelastic neutron scattering, and specific heat measurements

We report on a joint theoretical and experimental study of the vibrational dynamics of the type-I clathrates A8Sn44□2 (A = K, Rb, Cs, and □ stands for a vacancy) by high-resolution inelastic neutron

A theoretical study of 2D AlN on 3D C4H6N6Ni2 clathrate thermoelectric material composites

Clean and green renewable energy is of paramount importance in the world today. Ab initio calculations using density functional theory demonstrate that superlattice structures can result into

Microscopic Mechanisms of Glasslike Lattice Thermal Transport in Cubic Cu_{12}Sb_{4}S_{13} Tetrahedrites.

It is found that very strong phonon broadening leads to a qualitative breakdown of the conventional phonon-gas model and modify the dominant heat transport mechanism from the particlelike phonon wave packet propagation to incoherent contributions described by the off-diagonal terms in the heat-flux operator.

Evaluation of Thermoelectric Properties of Ag0.366Sb0.558Te

Ternary AgSbTe2 materials are frequently reported to show a promising thermoelectric performance, due to the intrinsically low lattice thermal conductivity and complex valence band structure.

Band and Phonon Engineering for Thermoelectric Enhancements of Rhombohedral GeTe.

AgBiSe2-alloying is found to not only finely manipulate the crystal structure for band convergence and thereby an increased band degeneracy, but also flatten the valence band for an increase band effective mass.

Unveiling the Correlation between the Crystalline Structure of M‐Filled CoSb3 (M = Y, K, Sr) Skutterudites and Their Thermoelectric Transport Properties

Skutterudite‐type pnictides based on CoSb3 are promising semiconductor materials for thermoelectric applications. An exhaustive structural characterization by synchrotron X‐ray powder diffraction of

Rational Electronic and Structural Designs Advance BiCuSeO Thermoelectrics

In this work, a record high thermoelectric figure‐of‐merit ZT of 1.6 ± 0.2 at 873 K in p‐type polycrystalline Bi0.94Pb0.06CuSe1.01O0.99 by a synergy of rational band manipulation and novel



Phonon-glass electron-crystal thermoelectric clathrates : Experiments and theory

Type-I clathrate compounds have attracted a great deal of interest in connection with the search for efficient thermoelectric materials. These compounds constitute networked cages consisting of

Nanostructured clathrate phonon glasses: beyond the rattling concept.

This work investigated the thermoelectric properties of a newly synthesized Si-based ternary clathrate K8Al8Si38, composed of ∼1 nm hollow cages with a metal atom inside and found that this system is a semiconductor and has a low thermal conductivity.

Phononic filter effect of rattling phonons in the thermoelectric clathrate Ba8Ge40+xNi6-x.

One of the key requirements for good thermoelectric materials is a low lattice thermal conductivity. Here we present a combined neutron scattering and theoretical investigation of the lattice

“Glass-like” thermal conductivity gradually induced in thermoelectric Sr8Ga16Ge30 clathrate by off-centered guest atoms

The origin of the “glass-like” plateau in thermal conductivity of inorganic type I clathrates has been debated for more than a decade. Here, it is demonstrated that the low temperature thermal

Avoided crossing of rattler modes in thermoelectric materials.

The phonon dispersion relation in the phonon glass-electron crystal material Ba(8)Ga(16)Ge(30) using neutron triple-axis spectroscopy is investigated, disclosing unambiguously the theoretically predicted avoided crossing of the rattler modes and the acoustic-phonon branches.

Direct measurement of individual phonon lifetimes in the clathrate compound Ba7.81Ge40.67Au5.33

The achievement of a direct quantitative measurement of phonon lifetimes in a single crystal of the clathrate Ba7.81Ge40.67Au5.33 is shown, underlining the inability of state-of-the-art simulations to reproduce the experimental data and representing a crucial experimental input for theoretical developments.

Impact of rattlers on thermal conductivity of a thermoelectric clathrate: a first-principles study.

Comparing phonon properties of filled and empty clathrates, it is shown that rattlers cause tenfold reductions in the relaxation time of phonons by increasing the phonon-phonon scattering probability.

Single-Crystal Investigations on Quaternary Clathrates Ba8Cu5SixGe41−x (x = 6, 18, 41)

Type I clathrates have been considered as promising thermoelectric materials due to their special structural characteristics: the “rattling” guest atoms in the larger of the two cages of the

Localization of propagative phonons in a perfectly crystalline solid.

The combined experimental and theoretical investigation of the lattice dynamics of a particularly simple binary representative, Ba(8)Si(46), identifies the mechanism responsible for the reduction of lattice thermal conductivity intrinsic to the perfect crystal structure.

Ba8Ga16Sn30 with type-I clathrate structure: Drastic suppression of heat conduction

For the past decade, intermetallic clathrates have been rattling their way into mainstream research in thermoelectrics. The unusual vibrations of their guest ions inside oversized cages interfere