Surface phononic graphene

Yu, Siyuan; Sun, Xiaochen; Ni, Xiaobo; Wang, Qing; Yan, Xuejun; He, Cheng; Liu, Xiaoping; Liang, Feng; Lu, Ming‐Hui; Chen, Yanfeng

doi:10.1038/nmat4743

Cited by 110 publications

(71 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The unique physics of Dirac quasiparticles can be mimicked in artificial graphene (AG) systems [1]. These AG systems include cold atom lattices [2][3][4][5][6], phononic crystals [7][8][9][10], photonic crystals [11][12][13][14][15][16], semiconductor nanopatterns [17][18][19][20][21][22] and molecular lattices assembled on metal surfaces, termed as molecular designers [23][24][25][26][27][28][29][30][31][32][33][34]. The tunability of the artificial systems makes them ideal playgrounds to exploit phenomena that are extremely challenging to access in real materials.…”

Section: Introductionmentioning

confidence: 99%

Symmetry breaking in molecular artificial graphene

et al. 2019

View full text Add to dashboard Cite

Symmetry breaking in graphene has profound impacts on its physical properties. Here we emulate symmetry breaking in artificial graphene systems by assembling coronene molecules on a Cu(111) surface. We apply two strategies: (1) differentiating the on-site energy of two sublattices of a honeycomb lattice and (2) uniaxially compressing a honeycomb lattice. The first one breaks the inversion symmetry while the second one merges the Dirac cones. The scanning tunneling spectroscopy shows that in both cases the local density of states undergo characteristic changes. Muffin-tin simulations reveal that the observed changes are associated with a band gap opened at the Dirac point. Furthermore, we propose that using larger molecules or molecules strongly scattering the surface state electrons can induce an indirect gap. Experimental and theoretical methodsSingle-crystal Cu(111) substrate was cleaned by cycles of Ar + sputtering and subsequently annealing to 530°C. The sample was characterized using an ultra-high vacuum (10 −10 mbar base pressure) scanning tunneling microscope (STM) system (Omicron GmbH) at cryogenic temperature (5 K). Coronene molecules (Sigma Aldrich) were thermally deposited at 290°C on the Cu(111) substrate held at room temperature and then OPEN ACCESS RECEIVED

show abstract

Section: Introductionmentioning

confidence: 99%

Symmetry breaking in molecular artificial graphene

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The system of classical waves can also have Dirac points, and hence Dirac-physics-related phenomena. Dirac points at the Brillouin zone boundary have been found in photonic and phononic crystals with honeycomb lattice [61][62][63] and many novel effects, such as pseudo-diffusion transport and Zitterbewegung, have been experimentally observed [15][16][17]64]. Compared with graphene, these artificial graphene systems have great advantages in flexible designing and high-fidelity measurements for quantum simulation of the Dirac equation.…”

Section: Dirac Physics and Reproduction Of Quantum Phenomena With Clamentioning

confidence: 99%

“…Compared with graphene, these artificial graphene systems have great advantages in flexible designing and high-fidelity measurements for quantum simulation of the Dirac equation. Here, we briefly introduce an artificial surface phononic graphene [17], which utilizes the surface acoustic wave (SAW) system to construct on-chip artificial graphene. SAW is an acoustic wave traveling along the surface of solids and decaying exponentially with depth into the substrate.…”

Section: Dirac Physics and Reproduction Of Quantum Phenomena With Clamentioning

confidence: 99%

“…These effects offered great potential for applications. More recently, the advent of graphene and its Dirac cones with linear dispersions have inspired the study and fabrication of phononic crystals with Dirac-quasiparticle-like behaviors that can experimentally reproduce quantum electronic phenomena such as Zitterbewegung and pseudodiffusion transport of acoustic waves [15][16][17]. Also, topological phases of matter [18,19] and the attendant concept of geometry, i.e.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Breaking the barriers: advances in acoustic functional materials

Yang

et al. 2017

National Science Review

Self Cite

190

View full text Add to dashboard Cite

Acoustics is a classical field of study that has witnessed tremendous developments over the past 25 years. Driven by the novel acoustic effects underpinned by phononic crystals with periodic modulation of elastic building blocks in wavelength scale and acoustic metamaterials with localized resonant units in subwavelength scale, researchers in diverse disciplines of physics, mathematics, and engineering have pushed the boundary of possibilities beyond those long held as unbreakable limits. More recently, structure designs guided by the physics of graphene and topological electronic states of matter have further broadened the whole field of acoustic metamaterials by phenomena that reproduce the quantum effects classically. Use of active energy-gain components, directed by the parity-time reversal symmetry principle, has led to some previously unexpected wave characteristics. It is the intention of this review to trace historically these exciting developments, substantiated by brief accounts of the salient milestones. The latter can include, but are not limited to, zero/negative refraction, subwavelength imaging, sound cloaking, total sound absorption, metasurface and phase engineering, Dirac physics and topology-inspired acoustic engineering, non-Hermitian parity-time synthetic active metamaterials, and one-way propagation of sound waves. These developments may underpin the next generation of acoustic materials and devices, and offer new methods for sound manipulation, leading to exciting applications in noise reduction, imaging, sensing and navigation, as well as communications.

show abstract

“…This leads many researchers to propose and study other artificial microscopic and even macroscopic graphene analogues for further fundamental studies. These settings include the use of molecules [5], ultracold atoms [6], photons [7][8][9][10] or phonons [11,12] in honeycomb lattice.…”

Section: Introductionmentioning

confidence: 99%

Granular graphene: Direct observation of edge states on zigzag and armchair boundaries

et al. 2019

View full text Add to dashboard Cite

We propose a mechanical graphene analogue which is made of stainless steel beads placed in a periodic magnetic field by a proper design. A stable, free of mechanical borders granular structure with well-predicted wave dynamics is experimentally constructed. First we report the dispersion relation in conjunction with the evidence of the Dirac points. Theoretical analysis shows that, compared to genuine or other artificial graphene analogues, unconventional edge modes exist in the free zigzag and armchair boundaries together with novel bulk modes composed of in-plane extended translations but localized rotations at the edges. We observe the existence of edge modes in free zigzag boundary, and we reveal an experimental robust turning effect of edge waves from the zigzag to the armchair/zigzag boundary, even in the absence of a full band gap for bulk modes. Our work shows that granular graphene can serve as an excellent experimental platform to study novel Dirac, topological and nonlinear wave phenomena.

show abstract

Surface phononic graphene

Cited by 110 publications

References 38 publications

Symmetry breaking in molecular artificial graphene

Symmetry breaking in molecular artificial graphene

Breaking the barriers: advances in acoustic functional materials

Granular graphene: Direct observation of edge states on zigzag and armchair boundaries

Contact Info

Product

Resources

About