Atomic, Molecular and Optical Physics
Attosecond science and nanophotonics Lab
Eugene Frumker
*Tracing and control of electronic motion in atoms, molecules, and nanostructures in space and time (4D). Progress in lightwave electronics. *Table-top XUV and soft X-ray laser-like sources. Nano-scale spatial resolution to optical science of attosecond pulses. *New dynamic imaging modalities – significantly improved spatial/temporal resolution, new contrast imaging for lifescience and nanotechnology. *And much more…
Biological and Soft Matter Physics
Mechanisms of Species Diversity Change in Stressed Environments
Ehud Meron
A transition from a banded vegetation pattern to a spotted pattern induced by a local clear-cut dis
The impacts of environmental changes on species diversity, and thus on ecosystem function and stability, is a central topic of current ecological research. At the landscape scale, where symmetry breaking vegetation patterns appear, a transition from one pattern state to another may take place (Animation). Using a mathematical modeling approach, we developed a theory of plant communities in water limited system, and are currently using it to highlight mechanisms of species diversity change in response to climate changes and disturbances.
Astrophysics and Cosmology
The largest objects: galaxy clusters
Uri Keshet
The Perseus cluster core (Chandra) with highlighted spiral cold fronts and X-ray cavities.
Galaxy clusters, as the largest virialized objects ever to form in the Universe, link cosmology and astrophysics. These 'island-universe' objects are mainly composed of dark matter and a hot, dilute plasma. Their stability is an open question, as the strong X-ray emission should have naively led to catastrophic cooling and collapse. Over the past decade, mysterious spiral structures were found in practically all clusters. They may be driven by the giant black hole lurking in the center of every cluster, for example through the relativistically hot bubbles it injects into the plasma (figure).
High-Energy Physics
Effective Theories and Quantum Gravity
Eran Palti
Effective theories are simplified physics models which neglect high-energy processes. If those theories include gravitational physics, then the omitted high-energy physics must include that of Quantum Gravity. Not all effective theories can be consistently completed at high energies into Quantum Gravity. Those which can are said to belong to the Landscape of effective theories. While those which cannot are said to belong to the Swampland of inconsistent theories. We study what are the criteria which differentiate an effective theory in the Landscape from one in the Swampland.
Condensed Matter Experimental
Mechanical properties on the nm scale
Yishay Manassen
Strain map from Gd islands and Local young modulus of nanoparticles.
The scanning tunneling microscope is a device capable of observing an image with atomic resolution and is capable of observing physical phenomena on the atomic scale. In this study we are interested in the nm scale mechanical properties, normally studied macroscopically, which can vary in different locations on the surface. These properties are the stress and strain tensors, the elastic constants, the surface energy and stress. These values can be measured either using a external perturbation (the STM tip) or internal perturbation (a heteroepitaxial island, chemical reaction).
Condensed Matter Theory
Non-equilibrium steady state of low-dimensional systems
Doron Cohen
It is possible to induce non-equilibrium steady state current, which required e.g. a radiation source. We have studied the non-monotonic dependence of the current on the intensity of the driving, and its statistical properties. We also have addressed questions that concern the relaxation of such current, and how it depends on percolation and localization properties of the model.