Unscrambling Structured Chirality with Structured Light at Nanoscale Using Photo-induced Force

Abstract

We introduce a microscopy technique that facilitates the prediction of spatial features of chirality of nanoscale samples by exploiting photo-induced optical force exerted on an achiral tip in the vicinity of the test specimen. The tip-sample interactive system is illuminated by structured light to probe both the transverse and longitudinal (with respect to the beam propagation direction) components of the sample magnetoelectric polarizability as the manifestation of its sense of handedness, i.e., chirality. We specifically prove that although circularly polarized waves are adequate to detect the transverse polarizability components of the sample, they are unable to probe the longitudinal component. To overcome this inadequacy, we propose a judiciously engineered combination of radially and azimuthally polarized beams, as optical vortices possessing pure longitudinal electric and magnetic field components along their vortex axis, respectively, hence probing longitudinal chirality. The proposed technique may benefit branches of science like stereochemistry, biomedicine, physical and material science, and pharmaceutics

References in corpus (13)

• An electromagnetic multipole expansion beyond the long-wavelength approximation
• Lateral Optical Force On Chiral Particles Near a Surface
• Determining polarizability tensors for an arbitrary small electromagnetic scatterer
• Generation of Vortex Beams with Strong Longitudinally Polarized Magnetic Field by Using a Metasurface
• Near-Field Nanoprobing Using Si Tip-Au Nanoparticle Photoinduced Force Microscopy with 120:1 Signal-to-Noise Ratio, Sub-6-nm Resolution
• Focused Azimuthally Polarized Vector Beam and Spatial Magnetic Resolution below the Diffraction Limit
• Enantio-specific Detection of Chiral Nano-Samples Using Photo-induced Force
• Optical Force and Torque on Dipolar Dual Chiral Particles
• Electric field enhancement with plasmonic colloidal nanoantennas excited by a silicon nitride waveguide
• Photo-induced Magnetic Force Between Nanostructures
• Optical Chirality of Time-Harmonic Wavefields for Classification of Scatterers
• Non-zero helicity extinction in light scattered from achiral (or chiral) small particles located at points of null incident helicity density
• Measurement of Laterally Induced Optical Forces at the Nanoscale

Cited by in corpus (6)

• Optimally Chiral Electromagnetic Fields: Helicity Density and Interaction of Structured Light with Nanoscale Matter
• Helicity Density Maximization in a Planar Array of Achiral High-Density Dielectric Nanoparticles
• Helicity Maximization Below the Diffraction Limit
• Helicity Maximization of Structured Light to Empower Nanoscale Chiral Matter Interaction
• The Azimuthally-Radially Polarized Beam: Helicity and Momentum Densities, Generation and Optimal Chiral Light
• Experimental generation of optimally chiral azimuthally-radially polarized beams