What is Condensed Matter Physics?
Condensed matter physics deals with many-body interacting systems. It provides a framework for describing and determining what happens to large groups of particles when they interact via known forces. Nature provides us with an almost unlimited variety of many-body systems, from dilute gases and quantum solids to living cells and quark-gluon plasmas. Collections of even the simplest atoms exist in a number of different states. Helium, for example, can be found not only in gaseous, liquid, and solid phases but also as a non-viscous superfluid at low temperatures. Condensed matter physics is the study of all of these many-body states of matter.
Condensed matter and materials science have played a key role in many of the scientific and technological revolutions that have changed our lives so dramatically in the last decades. Spectacular achievements have been driven by revolutionary advances in basic science of materials, such as polymeric, ceramic, and metallic materials, as well as the transistor, the magnetic disk, the laser, the light-emitting diode, and a host of other solid-state devices. The development of these materials and devices depended on our ability to predict and control the physical properties of matter. That ability is the realm of condensed matter and materials science.
Our condensed matter physics group is currently investigating a range of topics in fundamental and applied physics including unconventional superconductivity, quantum spin liquids, electron transport at low temperatures, semiconductor physics and semiconductor device properties at low temperatures, magnetism at ultralow temperatures, and physics of Josephson junction arrays. Our group members use a rich spectrum of experimental and theoretical techniques.
Who We Are
Dr. Sami El-Khatib:
My research interests have evolved from f-electron systems to complex magnetic oxides, the recurring themes being the study of correlated electron materials and the use of neutron scattering methods. I investigate the dual nature of f-electrons in strongly correlated electron systems, mainly in the lanthanides, actinides, and their compounds and alloys. Cobaltites and Manganites perovskite systems have been widely investigating through my research. These transition metals oxides have a very diverse range of physical properties from a wide variety of magnetic orderings to metal-insulator transitions, spin-state transitions, and the occurrence of high temperature superconductivity and colossal magnetoresistance. More recently, cobalt- based Heusler alloys are studied, nanoscale magnetic inhomogeneity amazingly leads to complicated blocking phenomena including decoupling of superparamagnetic and exchange bias blocking regions. I employed both macroscopic and microscopic techniques, I use multi-purpose PPMS, SQUID, XRD, transport measurements and different neutron scattering techniques.
Dr. Mehmet Egilmez:
Current research is focused on the technologically important materials with particular emphasis on magnetic/superconducting/semiconducting thin film hetero-structures. Our research benefits from various measurement techniques ranging from standard magneto-transport measurements to sophisticated Muon spin rotation/resonance measurements where local magnetic properties are probed. Our research is truly multidisciplinary and result of collaborative efforts. We collaborate extensively with well-known institutions located in United Kingdom, Canada and Switzerland.
Key words: Oxide thin film growth and surface characterization, magneto-transport measurements, Muon spin rotation/resonance measurements, Colossal magnetotransport phenomena, Triplet superconductivity
Dr. Nasser Hamdan:
Current research focuses on material science including perovskite and organic photovoltaics, high Tc superconductivity, semiconductors, environmental research and materials of cultural heritage.
Current research focuses on environmental materials science and aiming at source apportionment of particulate matter (PM) pollutants. We use X-Ray Diffraction, X-Ray florescence, RAMAN spectroscopy, synchrotron radiation and Scanning Electron Microscope (with EDX) in order to determine the elemental composition, chemical speciation and particulate size distribution of aerosols. Because we are the UAE counterpart in regional and international aerosol mapping projects sponsored by the International Atomic Energy Agency (IAEA) in Vienna, we are leading the country's research on particulate matter and air quality projects with the IAEA.
Key words: XRD, XRF, SEM/EDS, RAMAN, Nano materials, high temperature superconductivity, Organic Solar cells, synchrotron radiation.
Dr. Said Sakhi:
My research interest is at the interface between theoretical condensed matter physics and particle physics. I apply various techniques from quantum field theory to investigate strongly interacting systems such as quantum phase transitions in two dimensions, the fractional quantum Hall effect, quantum spin models, and the dynamics of Cooper pairs and vortices in Josephson junction arrays. Quantum phase transitions occur at absolute zero temperature and result from competing interactions that promote different ground states separated by a quantum critical point at which the system's degrees of freedom show anomalously large fluctuations on a long-wavelength scale compared with those of a normal system far from a critical point. These critical phenomena pose serious challenges because normal macroscopic laws are no longer valid in the vicinity of a critical point and novel ideas and methods must be invented to find the new laws that can describe the system. To that end I use methods that utilize the renormalization group formalism combined with either expansion around the system's critical dimension or large N expansion technique. Currently I am investigating the tricritical behavior in a theory of interacting multicomponent scalar fields with self-interactions up to sixth order and coupled to mixed Chern-Simons gauge fields. I am analyzing the quantum effective potential and the renormalization group functions of the various couplings using 1/N expansion technique. The goal is determine the stable infrared fixed points which control the long distance and low energy behavior of the system and the universal critical exponents.
Key words: Renormalization group, large-N technique, Chern-Simons theory, Ginzburg-Landau model.