Ultrafast coherent nonlinear nanooptics and nanoimaging of graphene

Jiang, Tongying; Kravtsov, Vasily; Tokman, M. D.; Belyanin, Alexey; Raschke, Markus B.

doi:10.1038/s41565-019-0515-x

Cited by 100 publications

(71 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The strong intrinsic field enhancement provided by the long‐lived and electrically tunable plasmons of monolayer graphene (cf. Section ) has naturally launched explorations of its ability to enhance nonlinear optical phenomena, stimulating fertile research efforts in nonlinear graphene plasmonics . Fortuitously, the unique linear electronic dispersion relation of graphene, giving rise to its universal 2.3% broadband light absorption and facile electrical tunability, also endows this 2D material with an intrinsically anharmonic response to external electromagnetic fields: low‐energy charge carriers within a single Dirac cone have energies ε k = ℏ v F | k |, where k is the electron wavevector and v F ≈ c /300 is the Fermi velocity, endowing them with a velocity of fixed magnitude that instantaneously changes sign when crossing the Dirac point; an applied ac electric field E ( t ) = E 0 cos( ωt ) thus leads to a square‐wave surface current density J ( t ) = − env F sign{sin ( ωt )} in the E 0 → ∞ limit that is weighted by the charge carrier density n and contains significant contributions from all odd harmonics in its Fourier decomposition (see Figure a) .…”

Section: Nonlinear Graphene Plasmonicsmentioning

confidence: 99%

Strong Light–Matter Interactions Enabled by Polaritons in Atomically Thin Materials

Gonçalves

Stenger

Cox

et al. 2020

Advanced Optical Materials

View full text Add to dashboard Cite

Polaritons, resulting from the hybridization of light with polarization charges formed at the boundaries between media with positive and negative dielectric response functions, can focus light into regions much smaller than its associated free‐space wavelength. This property is paramount for a plethora of applications in nanophotonics, ranging from biological sensing to photocatalysis to nonlinear and quantum optics. In the two‐dimensional (2D) limit, represented by atomically thin and van der Waals (vdW) materials of single‐layers bound by weak vdW attraction, polaritons are characterized by extremely small wavelengths associated with extreme optical confinement, and furthermore can exhibit long lifetimes, electrical tunability, and extreme sensitivity to their dielectric environment, among many other desirable qualities in nano‐optical device applications. Here, the fundamentals of polaritons in atomically thin materials are summarized, emphasizing plasmon and exciton polaritons, their strong light–matter interactions, and nonlinear plasmonics. More specifically, this review opens with a pedagogical discussion of plasmons in extended and nanostructured graphene, providing a classical electrodynamical model in a nonretarded theoretical framework, and the ultraconfined acoustic plasmons supported by hybrid graphene–dielectric–metal structures. In addition, the basic principles are introduced and the recent developments on nonlinear graphene plasmonics and on strong coupling physics with atomically thin transition metal dichalcogenides are reviewed. Finally, potentially new, promising research directions in the burgeoning field of 2D nanophotonics are identified.

show abstract

Section: Nonlinear Graphene Plasmonicsmentioning

confidence: 99%

Strong Light–Matter Interactions Enabled by Polaritons in Atomically Thin Materials

Gonçalves

Stenger

Cox

et al. 2020

Advanced Optical Materials

View full text Add to dashboard Cite

show abstract

“…Strong near-field enhancement at the tip apex may overcompensate the decrease in the volume of the material where light-matter interaction occurs [16,17]. This technique can provide information about surface states and carrier dynamics with about 10 nm spatial and 1 fs time resolution [17]. Even more importantly in the context of this paper, nanoscale concentration of the incident light at the tip apex relaxes the optical selection and momentum matching rules.…”

mentioning

confidence: 99%

“…Following the perturbation method detailed in [23], we use the Maxwell's equation The numerical values for the SP Poynting flux density in the plots were calculated at a distance of 250 µm from the tip and assuming that the excitation is created by the pump field of magnitude 10 6 V/cm localized within (10 nm) 3 . Such fields are far below damage threshold; for example, in experiments reported in [17] the pump field under the tip was estimated at 5 × 10 7 V/cm. Only 1/r divergence of the in-plane Poynting vector was included.…”

mentioning

confidence: 99%

Optical Hall effect and gyrotropy of surface polaritons in Weyl semimetals

et al. 2019

Self Cite

View full text Add to dashboard Cite

Weyl semimetals possess unique electrodynamic properties due to a combination of strongly anisotropic and gyrotropic bulk conductivity, surface conductivity, and surface dipole layer. We explore the potential of popular tip-enhanced optical spectroscopy techniques for studies of bulk and surface topological electron states in these materials. Anomalous dispersion, extreme anisotropy, and the optical Hall effect for surface polaritons launched by a nanotip provides information about Weyl node position and separation in the Brillouin zone, the value of the Fermi momentum, and the matrix elements of the optical transitions involving both bulk and surface electron states.

show abstract

“…This effect has been recently shown using large field gradients from tapered nanostructures [2,3]. Now Jiang et al have been able to enhance the third-order optical response in one to a few layers graphene using nanoscopic nonlinear near-field excitation [4]. The enhancement is a combination of the large momentum available in the plasmonic near-field and a Doppler shift broadening.…”

mentioning

confidence: 96%

Non-locality by nanoconfinement

Giugni

2019

Nat. Nanotechnol.

View full text Add to dashboard Cite

Non-locality by nanoconfinementCoherent ultrafast spectroscopy of nanofocused plasmonic pulses evidences a nonlinear optical phenomenon driven by the extra momentum available at the nanoscale and controlled by the Doppler effect. Andrea GiugniCurrent nanotechnology research in optoelectronics and nonlinear optics has heavily targeted twodimensional materials (2D), because they possess appealing electronic, optical, and plasmonic properties that, in many cases, can be conveniently tuned by external fields. These properties arise from the unconventional 2D atomic structure and quantum confinement effects of these materials, even though a rigorous theoretical explanation still remains elusive.

show abstract

Ultrafast coherent nonlinear nanooptics and nanoimaging of graphene

Cited by 100 publications

References 49 publications

Strong Light–Matter Interactions Enabled by Polaritons in Atomically Thin Materials

Strong Light–Matter Interactions Enabled by Polaritons in Atomically Thin Materials

Optical Hall effect and gyrotropy of surface polaritons in Weyl semimetals

Non-locality by nanoconfinement

Contact Info

Product

Resources

About