Core-shell architecture provides unique features to microparticles (MPs) by accurately selecting the employed materials. MPs with a mesogenic core and a metallic shell of gold nanoparticles (NPs) have been realized. The core is obtained by UV induced polymerization of reactive mesogens droplets in a chloroauric acid aqueous solution, whilst gold nanoparticles precipitation happens at the same time, covering the MPs surface. The MPs optical properties are modified by the gold shell, in the Bragg onion resonator condition when a chiral core is utilized, improving the laser emission stability compared to the MPs without shell. The proposed strategy, due to both the method and the versatility of the materials, suggests a new route to realize microdevices with wide control in term of intensity, polarization, generation [1]. The development of efficient micromachines is a challenge for applied and fundamental research. Light is a worthy mean to remotely displace micro-objects by inducing forces and torques. Rotational dynamics of core-shell MPs having ellipsoidal shape and nematic core is studied, and in particular a peculiar synchronous spin-orbital motion when the MPs are irradiated by a simple Gaussian beam. The observed effects originate from the coupling of the metallic NPs' optical response and the core anisotropies. The rotation performances strongly improve when trapping wavelength lie inside the plasmonic resonance range. In that case, spin kinetic energy achieves values two orders of magnitude larger than the one obtained from the bare MPs. The proposed approach bears important insights for design optimization in the MPs light driven motion, giving benefits to applications in microfluidics, microrheology, and micromachining that imply rotational dynamics [2]. [1] N. Pellizzi, A. Mazzulla, P. Pagliusi, G. Cipparrone, "Core-shell chiral polymeric-metallic particles obtained in a single step by concurrent light induced processes", Journal of Colloid and Interface Science 606:Part 1, 113-123 (2022) [2] N. Pellizzi, A. Mazzulla, P. Pagliusi, G. Cipparrone, "Plasmon-enhanced rotational dynamics of anisotropic core-shell polymeric-metallic microparticles", Photonics Research Journal, 10:12, 2734-2742 (2022).
Photonics and optomechanics of core-shell mesogenic-metallic particles
A Mazzulla;P Pagliusi;
2023
Abstract
Core-shell architecture provides unique features to microparticles (MPs) by accurately selecting the employed materials. MPs with a mesogenic core and a metallic shell of gold nanoparticles (NPs) have been realized. The core is obtained by UV induced polymerization of reactive mesogens droplets in a chloroauric acid aqueous solution, whilst gold nanoparticles precipitation happens at the same time, covering the MPs surface. The MPs optical properties are modified by the gold shell, in the Bragg onion resonator condition when a chiral core is utilized, improving the laser emission stability compared to the MPs without shell. The proposed strategy, due to both the method and the versatility of the materials, suggests a new route to realize microdevices with wide control in term of intensity, polarization, generation [1]. The development of efficient micromachines is a challenge for applied and fundamental research. Light is a worthy mean to remotely displace micro-objects by inducing forces and torques. Rotational dynamics of core-shell MPs having ellipsoidal shape and nematic core is studied, and in particular a peculiar synchronous spin-orbital motion when the MPs are irradiated by a simple Gaussian beam. The observed effects originate from the coupling of the metallic NPs' optical response and the core anisotropies. The rotation performances strongly improve when trapping wavelength lie inside the plasmonic resonance range. In that case, spin kinetic energy achieves values two orders of magnitude larger than the one obtained from the bare MPs. The proposed approach bears important insights for design optimization in the MPs light driven motion, giving benefits to applications in microfluidics, microrheology, and micromachining that imply rotational dynamics [2]. [1] N. Pellizzi, A. Mazzulla, P. Pagliusi, G. Cipparrone, "Core-shell chiral polymeric-metallic particles obtained in a single step by concurrent light induced processes", Journal of Colloid and Interface Science 606:Part 1, 113-123 (2022) [2] N. Pellizzi, A. Mazzulla, P. Pagliusi, G. Cipparrone, "Plasmon-enhanced rotational dynamics of anisotropic core-shell polymeric-metallic microparticles", Photonics Research Journal, 10:12, 2734-2742 (2022).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
