Truly chiral phonons in α-HgS

Ishito, Kyosuke; Mao, Huiling; Kousaka, Yusuke; Togawa, Yoshihiko; Iwasaki, Satoshi; Zhang, Tiantian; Murakami, Shuichi; Kishine, Jun‐ichiro; Satoh, Takuya

doi:10.1038/s41567-022-01790-x

Cited by 66 publications

(36 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The frequency differences between the RL and LR peaks of Samples 1 and 2 and those in Pine and Dresselhaus 35 are listed in Table 2. Such splitting has also been observed in Raman spectroscopy in

α

‐quartz, 50,51 Te, 35 and

α

‐HgS 11 …”

Section: Resultssupporting

confidence: 57%

“…Some parts of the surface were tilted from the c-axis-oriented surface because of the rough surface. We verified the spin PAM conservation law 11 for the Raman scattering process as follows:…”

Section: Discussionmentioning

confidence: 99%

“…2,25 A combination of Γ 3 mode splitting in chiral materials and spin PAM assignment enables us to determine the handedness of other chiral materials, such as α-quartz and α-HgS. 11…”

Section: Discussionmentioning

confidence: 99%

“…For example, R-Te is C 3 j1=3 f g invariant, where C 3 j1=3 f g indicates C 3 rotation around the c axis and c=3 translation along the c axis. Therefore, the spin PAM of phonon m s PAM ðRH, kÞ of branch j at wavenumber k in R-Te is defined as 11,33 C 3 jc=3 f guðRH, kÞ Similarly, the spin PAM of the phonon m s PAM ðLH,kÞ of branch j at wavenumber k in L-Te is defined as 11,33 C 3 j2c=3 f g uðLH, kÞ…”

Section: Ab Initio Calculation and The Am Analysis Of The Phononmentioning

confidence: 99%

“…The PAM of the phonon takes a quantized value originating from a phase change of a wave function acquired by a discrete rotation operation 3 and is essential for conservation laws in light scattering 8,9 and transport physics 10 . The AM of a phonon has a continuous value calculated by the atomic circular motion and has been reported in binary crystals such as

α

‐HgS 11 and ABi (A = K, Rb, Cs), 12 whereas that in unary crystals has not been reported.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Chiral phonons: circularly polarized Raman spectroscopy and ab initio calculations in a chiral crystal tellurium

et al. 2023

Self Cite

View full text Add to dashboard Cite

Recently, phonons with chirality (chiral phonons) have attracted significant attention. Chiral phonons exhibit angular and pseudoangular momenta. In circularly polarized Raman spectroscopy, the peak split of the normalΓ3 mode is detectable along the principal axis of the chiral crystal in the backscattering configuration. In addition, peak splitting occurs when the pseudoangular momenta of the incident and scattered circularly polarized light are reversed. Until now, chiral phonons in binary crystals have been observed, whereas those in unary crystals have not been observed. Here, we observe chiral phonons in a chiral unary crystal Te. The pseudoangular momentum of the phonon is obtained in Te by an ab initio calculation. From this calculation, we verified the conservation law of pseudoangular momentum in Raman scattering. From this conservation law, we determined the handedness of the chiral crystals. We also evaluated the true chirality of the phonons using a measure with symmetry similar to that of an electric toroidal monopole.

show abstract

α

‐quartz, 50,51 Te, 35 and

α

‐HgS 11 …”

Section: Resultssupporting

confidence: 57%

Section: Discussionmentioning

confidence: 99%

“…2,25 A combination of Γ 3 mode splitting in chiral materials and spin PAM assignment enables us to determine the handedness of other chiral materials, such as α-quartz and α-HgS. 11…”

Section: Discussionmentioning

confidence: 99%

Section: Ab Initio Calculation and The Am Analysis Of The Phononmentioning

confidence: 99%

α

‐HgS 11 and ABi (A = K, Rb, Cs), 12 whereas that in unary crystals has not been reported.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Chiral phonons: circularly polarized Raman spectroscopy and ab initio calculations in a chiral crystal tellurium

et al. 2023

Self Cite

View full text Add to dashboard Cite

show abstract

Observation of Chirality‐Induced Roton‐Like Dispersion in a 3D Micropolar Elastic Metamaterial

Chen

Schneider

Wang

et al. 2023

Adv Funct Materials

View full text Add to dashboard Cite

A theoretical paper based on chiral micropolar effective‐medium theory suggested the possibility of unusual roton‐like acoustical‐phonon dispersion relations in 3D elastic materials. Here, as a first novelty, the corresponding inverse problem is solved, that is, a specific 3D chiral elastic metamaterial structure is designed, the behavior of which follows this effective‐medium description. The metamaterial structure is based on a simple‐cubic lattice of cubes, each of which not only has three translational but also three rotational degrees of freedom. The additional rotational degrees of freedom are crucial within micropolar elasticity. The cubes and their degrees of freedom are coupled by a chiral network of slender rods. As a second novelty, this complex metamaterial is manufactured in polymer form by 3D laser printing and its behavior is characterized experimentally by phonon‐band‐structure measurements. The results of these measurements, microstructure finite‐element calculations, and solutions of micropolar effective‐medium theory are in good agreement. The roton‐like dispersion behavior of the lowest phonon branch results from two aspects. First, chirality splits the transverse acoustical branches as well as the transverse optical branches. Second, chirality leads to an ultrastrong coupling and hybridization of chiral acoustical and optical phonons at finite wavevectors.

show abstract

Nonequivalent Atomic Vibrations at Interfaces in a Polar Superlattice

Hoglund,

Walker,

Hussain

et al. 2024

Advanced Materials

View full text Add to dashboard Cite

In heterostructures made from polar materials, e.g., AlN‐GaN‐AlN, the non‐equivalence of the two interfaces has long been recognized as a critical aspect of their electronic properties, in that they host different two‐dimensional carrier gases. Interfaces play an important role in the vibrational properties of materials, where interface states enhance thermal conductivity and can generate unique infrared‐optical activity. The non‐equivalence of the corresponding interface atomic vibrations, however, has not been investigated so far due to a lack of experimental techniques with both high spatial and high spectral resolution. Herein we experimentally demonstrate the non‐equivalence of AlN‐(Al0.65Ga0.35)N and (Al0.65Ga0.35)N‐AlN interface vibrations using monochromated electron energy‐loss spectroscopy in the scanning transmission electron microscope (STEM‐EELS) and employ density‐functional‐theory (DFT) calculations to gain insights in the physical origins of observations. We demonstrate that STEM‐EELS possesses sensitivity to the displacement vector of the vibrational modes as well as the frequency, which is as critical to understanding vibrations as polarization in optical spectroscopies. The combination enables direct mapping of the non‐equivalent interface phonons between materials with different phonon polarizations. The results demonstrate the capacity to carefully assess the vibrational properties of complex heterostructures where interface states dominate the functional properties.This article is protected by copyright. All rights reserved

show abstract

Truly chiral phonons in α-HgS

Cited by 66 publications

References 38 publications

Chiral phonons: circularly polarized Raman spectroscopy and ab initio calculations in a chiral crystal tellurium

Chiral phonons: circularly polarized Raman spectroscopy and ab initio calculations in a chiral crystal tellurium

Observation of Chirality‐Induced Roton‐Like Dispersion in a 3D Micropolar Elastic Metamaterial

Nonequivalent Atomic Vibrations at Interfaces in a Polar Superlattice

Contact Info

Product

Resources

About