Exciting a chiral dipole moment in an achiral nanostructure

Eismann, Jörg S.; Neugebauer, Martin; Banzer, Peter

doi:10.1364/optica.5.000954

Cited by 56 publications

(49 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…With our scheme we now show experimentally and theoretically that tightly focused linearly polarized LG ±1 0 beams provide the necessary condition for a dipole-like chiral particle to scatter differently for different vorticities of the input beam via the creation of longitudinal field components on the optical axis and the resulting optical chirality. Hence, we take advantage of non-paraxial propagation of structured light and the corresponding longitudinal field components created at the focal plane [9,24]. In our experiment, we utilize a plasmonic nanohelix as a prototypical chiral scatterer (see Fig.…”

Section: Beamsmentioning

confidence: 99%

Interaction of light carrying orbital angular momentum with a chiral dipolar scatterer

Woźniak¹,

León²,

Höflich³

et al. 2019

Optica

Self Cite

View full text Add to dashboard Cite

The capability to distinguish the handedness of circularly polarized light is a well-known intrinsic property of a chiral nanostructure. It is a long-standing controversial debate, however, whether a chiral object can also sense the vorticity, or the orbital angular momentum (OAM), of a light field. Since OAM is a non-local property, it seems rather counter-intuitive that a point-like chiral object could be able to distinguish the sense of the wave-front of light carrying OAM. Here, we show that a dipolar chiral nanostructure is indeed capable of distinguishing the sign of the phase vortex of the incoming light beam. To this end, we take advantage of the conversion of the sign of OAM, carried by a linearly polarized Laguerre-Gaussian beam, into the sign of optical chirality upon tight focusing. Our study provides for a deeper insight into the discussion of chiral light-matter interactions and the respective role of OAM.

show abstract

Section: Beamsmentioning

confidence: 99%

Interaction of light carrying orbital angular momentum with a chiral dipolar scatterer

Woźniak¹,

León²,

Höflich³

et al. 2019

Optica

Self Cite

View full text Add to dashboard Cite

show abstract

“…On the contrary, in the angular range 0.9≤NA≤1.3, corresponding to the scattered light only, we obtain negligible values of S 3 ≈0. The small (but non-zero) residual values in the angular range 0.9≤NA≤1.3 originate from the contribution of a small (but not strictly zero) magnetic dipole moment [23] supported by the gold nanoparticle.…”

Section: Methodsmentioning

confidence: 97%

“…Our experimental setup, described in detail in our previous works [23,35], is shown as a simplified sketch in Fig. 2(a).…”

Section: Methodsmentioning

confidence: 99%

“…Here, we present a counter-intuitive case of interaction between an electric-dipole scatterer and achiral light in cylindrically symmetric configuration that results in generation of circular polarization, effectively mimicking an interaction of matter and light chirality. Specifically, we show that scattering of a focused cylindrical vector beam with spiral polarization [22,23] by an electric-dipole scatterer generates far-field helicity. Notwithstanding that * sergey.nechayev@mpl.mpg.de the incident beam, the focal fields, as well as the scattered light bear zero optical chirality and the scatterer is positioned on the optical axis -the axis of rotational symmetry of the system.…”

Section: Introductionmentioning

confidence: 98%

See 1 more Smart Citation

Mimicking chiral light-matter interaction

Nechayev

Banzer

2019

Phys. Rev. B

Self Cite

View full text Add to dashboard Cite

We demonstrate that electric-dipole scatterers can mimic chiral light-matter interaction by generating far-field circular polarization upon scattering, even though the optical chirality of the incident field as well as that of the scattered light is zero. The presented effect originates from the fact that electric-dipole scatterers respond selectively only to the incident electric field, which eventually results in depolarization of the transmitted beam and in generation of far-field circular polarization. To experimentally demonstrate this effect we utilize a cylindrical vector beam with spiral polarization and a spherical gold nanoparticle positioned on the optical axis -the axis of rotational symmetry of the system. Our experiment and a simple theoretical model address the fundamentals of duality symmetry in optics and chiral light-matter interactions, accentuating their richness and ubiquity yet in highly symmetric configurations.

show abstract

“…5. An experimental far-field multipolar analysis (see, e.g., [63]) can help in identifying the modes, also making possible a quantitative analysis of the Raman spectra recorded with PETERS.…”

Section: Towards Quantitative Measurements and Data Analysismentioning

confidence: 99%

Towards polarization-based excitation tailoring for extended Raman spectroscopy

et al. 2020

Self Cite

View full text Add to dashboard Cite

Undoubtedly, Raman spectroscopy is one of the most elaborated spectroscopy tools in materials science, chemistry, medicine and optics. However, when it comes to the analysis of nanostructured specimens, accessing the Raman spectra resulting from an exciting electric field component oriented perpendicularly to the substrate plane is a difficult task and conventionally can only be achieved by mechanically tilting the sample, or by sophisticated sample preparation. Here, we propose a novel experimental method based on the utilization of polarization tailored light for Raman spectroscopy of individual nanostructures. As a proof of principle, we create three-dimensional electromagnetic field distributions at the nanoscale using tightly focused cylindrical vector beams impinging normally onto the specimen, hence keeping the conventional beam-path of commercial Raman systems. Using this excitation scheme, we experimentally show that the recorded Raman spectra of individual gallium-nitride nanostructures of sub-wavelength diameter used as a test platform depend sensitively on their location relative to the focal vector field. The arXiv:1905.12325v1 [physics.optics] 29 May 2019 observed Raman spectra can be attributed to the interaction with transverse or longitudinal electric field components. This novel technique may pave the way towards a characterization of Raman active nanosystems using full information of all Raman modes.

show abstract

Exciting a chiral dipole moment in an achiral nanostructure

Cited by 56 publications

References 37 publications

Interaction of light carrying orbital angular momentum with a chiral dipolar scatterer

Interaction of light carrying orbital angular momentum with a chiral dipolar scatterer

Mimicking chiral light-matter interaction

Towards polarization-based excitation tailoring for extended Raman spectroscopy

Contact Info

Product

Resources

About