Related papers: Minimizing the Ground Effect for Photophoretically…
Scaling down miniature rotorcraft and flapping-wing flyers to sub-centimeter dimensions is challenging due to complex electronics requirements, manufacturing limitations, and the increase in viscous damping at low Reynolds numbers.…
We report light-driven levitation of macroscopic polymer films whose bottom surface is engineered to maximize the thermal accommodation coefficient. Specifically, we levitated centimeter-scale disks made of commercial 0.5-micron-thick mylar…
Photophoretic forces could levitate thin 10 centimeter-scale structures in Earth's stratosphere indefinitely. We develop analytical models of the thermal transpiration force on a bilayer sandwich structure in the stratosphere. Lofting is…
The goal of ultrathin lightweight photophoretic flyers, or light-flyers for short, is to levitate continuously in Earth's upper atmosphere using only sunlight for propulsive power. We previously reported light-flyers that levitated by…
Photophoretic forces, several orders of magnitude stronger than radiation pressure, enable particle trapping at remarkably low optical intensities and have opened pathways to applications in aerosol science, free-space 3D volumetric…
As platform size is reduced, the flight of aerial robots becomes increasingly energetically expensive. Limitations on payload and endurance of these small robots have prompted researchers to explore the use of bimodal aerial-surface…
We show that photophoretic aircraft would greatly benefit from a three-dimensional (3D) hollow geometry that pumps ambient air through sidewalls to create a high-speed jet. To identify optimal geometries, we developed a theoretical…
Laser has become a powerful tool to manipulate micro-particles and atoms by radiation pressure force or photophoretic force, but optical manipulation is less noticeable for large objects. Optically-induced negative forces have been proposed…
In optically thin parts of protoplanetary disks photophoresis is a significant force not just for dust grains, but also for macroscopic bodies. The absolute strength on the supposedly highly porous objects is not known in detail as yet. We…
The electrical environment of a ground vacuum testing chamber creates facility effects for gridded ion thrusters. For example, it is well known that the plume from the thruster generates current paths that are very different from what…
Conducting levitated mechanical experiments in extreme conditions has long been the aim of researchers, as it allows for the investigation of new fundamental physics phenomena. One of the great frontiers has been sending these experiments…
Levitation of microscopic objects in vacuum combines exceptional environmental isolation with precise control of their dynamics, pushing the limits of sensing and macroscopic quantum physics. In particular, magnetic levitation allows a…
This paper presents a novel approach to launch single microparticles at high velocities under low vacuum conditions. In an all-optical table-top method, microparticles with sizes ranging from a few microns to tens of microns are accelerated…
Levitated optomechanical systems are rapidly becoming leading tools for precision sensing of forces and accelerations acting on particles in the femtogram to nanogram mass range. These systems enable a high level of control over the…
Levitation in vacuum has evolved into a versatile technique which has already benefited diverse scientific directions, from force sensing and thermodynamics to material science and chemistry. It also holds great promises of advancing the…
Photophoretic motion can transport illuminated particles in protoplanetary disks. In a previous paper we focused on the modeling of steady state photophoretic forces based on the compositions derived from tomography and heat transfer. Here,…
Levitated dielectric particles in a vacuum have emerged as a new platform in quantum science, with applications ranging from precision acceleration and force sensing to testing quantum physics beyond the microscopic domain. Traditionally,…
In this paper, we present a new experimental facility, Little Earth Experiment, designed to study the hydrodynamics of liquid planetary cores. The main novelty of this apparatus is that a transparent electrically conducting electrolyte is…
The control of levitated nano- and micro-objects in vacuum is of considerable interest, capitalizing on the scientific achievements in the fields of atomic physics, control theory and optomechanics. The ability to couple the motion of…
Aerodynamic ground effect in flapping-wing insect flight is of importance to comparative morphologies and of interest to the micro-air-vehicle (MAV) community. Recent studies, however, show apparently contradictory results of either some…