Optothermal rotation of micro-/nano-objects

Abstract

Due to its contactless and fuel-free operation, optical rotation of micro-/nano-objects provides tremendous opportunities for cellular biology, three-dimensional (3D) imaging, and micro/nanorobotics. However, complex optics, extremely high operational power, and...

Optical Manipulation Heats up: Present and Future of Optothermal Manipulation

“…43 Optothermal manipulation, on the other hand, can achieve the rotation of various particles with simple optics by integrating multiple optothermal forces on the particle. 44 The in-plane optothermal rotation can be induced by different thermal forces such as thermoelectricity or thermodiffusion (Figure 2j,k). 38,45 As for more complicated out-of-plane rotation, Ding et al successfully broke the symmetry of the particles by introducing the thermo-electrokinetic effects from the substrate and achieved a wide range of out-of-plane rotation of synthetic colloids and biological cells (Figure 2l,m) with a single laser beam.…”

“…Rotational manipulation mode requires the altering of the force and energy landscape in the plane perpendicular to the vector connecting particle center and laser focus. , While optical tweezers can achieve rotation of particles, they often require asymmetric particles or a dual counterpropagating beam . Optothermal manipulation, on the other hand, can achieve the rotation of various particles with simple optics by integrating multiple optothermal forces on the particle . The in-plane optothermal rotation can be induced by different thermal forces such as thermoelectricity or thermodiffusion (Figure j,k). , As for more complicated out-of-plane rotation, Ding et al successfully broke the symmetry of the particles by introducing the thermo-electrokinetic effects from the substrate and achieved a wide range of out-of-plane rotation of synthetic colloids and biological cells (Figure l,m) with a single laser beam .…”

Optical Manipulation of Fibroblasts with Femtosecond Pulse and CW Laser

“…In addition, a number of impressive studies, including the manipulation of red blood cells within the capillaries of living animals [24], the measurement of intercellular adhesion and anti-adhesion forces [25], and the use of lipid droplets as endogenous intracellular microlenses for real-time monitoring of subcellular structures and extracellular signals [26], have also been realized based on optical tweezers. As a result of scientific and technological advances, various kinds of optical tweezers, such as holographic optical tweezers [27], plasmonic optical tweezers [28], fiber optical tweezers [29], and optothermal tweezers [30], have demonstrated the ability to manipulate particles or cells directly or indirectly utilizing optical forces and energy [31].…”

Emergence of Directional Rotation in an Optothermally Activated Colloidal System

“…One of the ways to do so is to utilize optothermal effects, where localized optical heating can create asymmetric temperature gradients, thereby breaking the symmetry that results in rotation. − ,− To gain control over this approach, it is now imperative to identify the material parameters of thermally active colloids and the nature of optothermal fields that generate rotation. Specifically, generating directional rotation in the artificial active matter has emerged as an important task, ,, which needs attention for both fundamental understanding and biological and technological applications.…”