Biological and Soft Matter Physics
Internal dynamics of biological polymers: DNA molecules, actin filaments
Oleg Krichevsky
The dynamics of a semi-flexible polymer
The problem of polymer dynamics is rather old, going back to the 1930-s. How the stochastic thermal motion (diffusion) reveals itself in the dynamics of polymer segments which are bound by connectivity along the chain, by polymer stiffness, by topological constrains, by hydrodynamic and other interactions? The question does not have simple solutions in neither theory, computer simulations, or experiments. We have developed an original experimental approach to measure the dynamics of biological polymers, such as DNA at the level of single monomer with high temporal and spatial resolution.
Condensed Matter Experimental
Noise in strongly correlated systems
Grzegorz Jung
Normalized spectral density and R(T) for distinct resistivity states
To many physicist the subject of fluctuations appears esoteric and even pointless; spontaneous fluctuations seem nothing but an unwanted evil which only an unwise experimenter would encounter. In reality, noise enables a deep insight into physics of the system. Recently, we have employed noise to discriminate various resistivity states in the ferromagnetic insulating manganite La0.86Ca0.14MnO3. Different states arise due to transitions between local minima of the electronic glass potential landscape. Remarkably, freezing into the glass state is marked by the onset of non-Gaussian noise.
Atomic, Molecular and Optical Physics
Attosecond Science and Nanophotonics Lab
Eugene Frumker
We are setting up a brand-new research laboratory of Attosecond Science and Nanophotonics in the Physics Department of the Ben-Gurion University. In our group, we focus on both experimental and theoretical studies at the interface of ultrafast nonlinear optics, attosecond science and nanoscience. More specifically, our work involves generation, measurement and control of the interaction of light and matter in atoms, molecules and nanosystems in space and time at extremely short (attosecond=10^(-18)sec) time scales. Our interests range from fundamental physical phenomena to applications.
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).
Condensed Matter Theory
Superfluidity and thermalization in low dimensional Bose-Hubbard circuits
Doron Cohen
Circuits with condensed bosons can support superflow. Such circuits, if realized, will be used as QUBITs (for quantum computation) or as SQUIDs (for sensing of acceleration or gravitation). We are studying the feasibility and the design considerations for such devices. The key is to develop a theory for the superfluidity in an atomtronic circuit. Such theory goes beyond the traditional framework of Landau and followers, since is involves ''Quantum chaos'' considerations.
High-Energy Physics
QCD at High Energies
Michael Lublinsky
Different resolution of the proton structure as probed by virtual photons in ep collisions.
We have entered the fascinating era of the Large Hadron Collider. The microscopic theory describing the structure of protons and nuclei is the theory of strong interactions, known as Quantum ChromoDynamics (QCD). Even though the fundamental theory is known, it is extremely difficult to deduce results of collision processes from first principle QCD calculations. This is due to complexity of the theory involving mutual interactions between gluons, the "photons" of strong interactions.