Related papers: Algal Optics
A swimming microorganism stirs the surrounding fluid, creating a flow field that governs not only its locomotion and nutrient uptake, but also its interactions with other microorganisms and the environment. Despite its fundamental…
Deposits from evaporating drops have shown to take a variety of shapes, depending on the physicochemical properties of both solute and solvent. Classically, the evaporation of drops of colloidal suspensions leads to the so-called coffee…
Geometrical optics is extended so as to provide a model for spinning light rays via the coadjoint orbits of the Euclidean group characterized by color and spin. This leads to a theory of ``geometrical spinoptics'' in refractive media.…
Swimming at a micrometer scale demands particular strategies. Indeed when inertia is negligible as compared to viscous forces (i.e. Reynolds number $Re$ is lower than unity), hydrodynamics equations are reversible in time. To achieve…
Phototaxis is a light driven self-locomotion of mass and a common phenomenon in motile organisms with varieties of motility such as in bacteria, algae, etc. In naturally occurring organisms, mechanical force is generated utilising their…
Diffraction limits the behaviour of light in optical systems and sets the smallest achievable line width at half the wavelength. With a novel subwavelength plasmonic lens to reduce the diffraction via an asymmetry and to generate and…
Suspensions of motile microorganisms can spontaneously form large-scale fluid motion, known as bioconvection, characterized by dense downwelling plumes separated by broad upwelling regions. In this study, we investigate bioconvection in…
Plants have developed intricate mechanisms to adapt to changing light conditions. Besides photo- and helio- tropism -- the differential growth towards light and the diurnal motion with respect to sunlight -- chloroplast motion acts as a…
The incessant activity of swimming microorganisms has a direct physical effect on surrounding microscopic objects, leading to enhanced diffusion far beyond the level of Brownian motion with possible influences on the spatial distribution of…
Reflection and refraction of light can be used to trap small dielectric particles in the geometrical optics regime. Absorption of light is usually neglected in theoretical calculations, but it is known that it occurs in the optical trapping…
Advances in fluorescence microscopy have reached a plateau in improving depth-to-resolution ratios for imaging scattering tissues, highlighting an urgent need for innovative techniques. We introduce Wavelens, a groundbreaking opaque lens…
A fundamental issue in biology is the nature of evolutionary transitions from unicellular to multicellular organisms. Volvocine algae are models for this transition, as they span from the unicellular biflagellate Chlamydomonas to…
Light gradient can allow many motile photosynthetic microorganisms to bias their motion towards moderate light (positive phototaxis) or away from intense light (negative phototaxis). The proposed work presents the penetrative phototactic…
Due to the highly inhomogeneous distributions of refractive indexes, light propagation in complex media such as biological tissue experiences multiple light scattering events. The suppression and control of multiple light scattering events…
The potential of industrial applications for microalgae has motivated their recent fast development. Their growth dynamics depends on different factors that must be optimized. Since they get their energy from photosynthesis, light is a key…
Marine microalgae are widespread in the ocean and play a crucial role in the ecosystem. Automatic identification and location of marine microalgae in microscopy images would help establish marine ecological environment monitoring and water…
In this study, we analyze the bioconvection in a suspension of phototactic algae that exhibits anisotropic scattering. The top layer of the suspension is illuminated by oblique collimated irradiation. During the study, the bottom boundary…
The impact of rotation on the bio-convective instability in a phototactic algal suspension is investigated through a linear stability analysis in this article. The study primarily focuses on the suspension's phototactic behavior, which…
The single Anti-Reflecting (AR) layer is a classical problem in optics. When all materials are pure dielectrics, the solution is the so-called lambda/4 layer. Here we examine the case of absorbing layers between non absorbing media. We find…
The onset of light-induced bioconvection via linear stability theory is investigated qualitatively for a suspension of phototactic algae. The forward scattering algal suspension is uniformly illuminated by both diffuse and oblique…