User profiles for R. Wittkowski

Raphael Wittkowski

Assistant Professor of Physics, Westfälische Wilhelms-Universität Münster, Germany
Verified email at wwu.de
Cited by 4266

Phase-field-crystal models for condensed matter dynamics on atomic length and diffusive time scales: an overview

H Emmerich, H Löwen, R Wittkowski, T Gruhn… - Advances in …, 2012 - Taylor & Francis
Here, we review the basic concepts and applications of the phase-field-crystal (PFC) method,
which is one of the latest simulation methodologies in materials science for problems, …

Classical dynamical density functional theory: from fundamentals to applications

M te Vrugt, H Löwen, R Wittkowski - Advances in Physics, 2020 - Taylor & Francis
… ( r → ) with position r → . Classical DFT has found many applications in soft matter physics.
… They describe the time evolution of the one-body density ρ ( r → , t ) with time t using a …

[HTML][HTML] Aggregated aluminium exposure: risk assessment for the general population

…, M Greiner, A Lampen, A Luch, R Wittkowski… - Archives of …, 2019 - Springer
Aluminium is one of the most abundant elements in earth’s crust and its manifold uses result
in an exposure of the population from many sources. Developmental toxicity, effects on the …

[HTML][HTML] Scalar φ4 field theory for active-particle phase separation

R Wittkowski, A Tiribocchi, J Stenhammar… - Nature …, 2014 - nature.com
… 2, we establish that to leading order in large R (that is, small |λ|), … of droplets, each with radius
R*, embedded in a continuous … B a stationary value of the droplet radius R 0 exists for μ>0, …

Circular motion of asymmetric self-propelling particles

…, B Ten Hagen, R Wittkowski, I Buttinoni, R Eichhorn… - Physical review …, 2013 - APS
… and v, the radius R of the circular trajectories becomes independent of the propulsion speed…
and (b) radius R of the circular motion of an Lþ swimmer plotted as functions of the linear …

Pressure and phase equilibria in interacting active Brownian spheres

AP Solon, J Stenhammar, R Wittkowski, M Kardar… - Physical review …, 2015 - APS
We derive a microscopic expression for the mechanical pressure P in a system of spherical
active Brownian particles at density ρ. Our exact result relates P, defined as the force per unit …

Activity-induced phase separation and self-assembly in mixtures of active and passive particles

J Stenhammar, R Wittkowski, D Marenduzzo… - Physical review letters, 2015 - APS
We investigate the phase behavior and kinetics of a monodisperse mixture of active (ie, self-propelled)
and passive isometric Brownian particles through Brownian dynamics …

[HTML][HTML] Roadmap for optical tweezers

…, Y Roichman, V Bobkova, R Wittkowski… - Journal of Physics …, 2023 - iopscience.iop.org
Optical tweezers are tools made of light that enable contactless pushing, trapping, and
manipulation of objects, ranging from atoms to space light sails. Since the pioneering work by …

[HTML][HTML] Gravitaxis of asymmetric self-propelled colloidal particles

B Ten Hagen, F Kümmel, R Wittkowski, D Takagi… - Nature …, 2014 - nature.com
… with identical mass density but different radii R 1 and R 2 >R 1 . The sedimentation speed
of a single sphere with radius R due to gravitational and viscous forces is υ∝R 2 . Therefore, if …

An acoustically controlled helical microrobot

Y Deng, A Paskert, Z Zhang, R Wittkowski… - Science …, 2023 - science.org
… To characterize the width, we introduce as a dimensionless parameter the effective radius
ratio (r d = r/R), which describes the ratio of the radius r of the microrobot’s cylindrical core to …