Condensed matter physics is the field of physics that deals with the macroscopic and microscopic physical properties of matter, especially the solid and liquid phases which arise from electromagnetic forces between atoms. More generally, the subject deals with "condensed" phases of matter: systems of many constituents with strong interactions between them. More exotic condensed phases include the superconducting phase exhibited by certain materials at low temperature, the ferromagnetic and antiferromagnetic phases of spins on crystal lattices of atoms, and the Bose–Einstein condensate found in ultracold atomic systems. Condensed matter physicists seek to understand the behavior of these phases by experiments to measure various material properties, and by applying the physical laws of quantum mechanics, electromagnetism, statistical mechanics, and other theories to develop mathematical models.
Diamagnetic materials are repelled by a magnetic field; an applied magnetic field creates an induced magnetic field in them in the opposite direction, causing a repulsive force. In contrast, paramagnetic and ferromagnetic materials are attracted by a magnetic field. Diamagnetism is a quantum mechanical effect that occurs in all materials; when it is the only contribution to the magnetism, the material is called diamagnetic. In paramagnetic and ferromagnetic substances, the weak diamagnetic force is overcome by the attractive force of magnetic dipoles in the material. The magnetic permeability of diamagnetic materials is less than the permeability of vacuum, μ0. In most materials, diamagnetism is a weak effect which can be detected only by sensitive laboratory instruments, but a superconductor acts as a strong diamagnet because it repels a magnetic field entirely from its interior.
Ferromagnetism is a property of certain materials that results in a significant, observable magnetic permeability, and in many cases, a significant magnetic coercivity, allowing the material to form a permanent magnet. Ferromagnetic materials are familiar metals that are noticeably attracted to a magnet, a consequence of their substantial magnetic permeability. Magnetic permeability describes the induced magnetization of a material due to the presence of an external magnetic field. This temporarily induced magnetization, for example, inside a steel plate, accounts for its attraction to the permanent magnet. Whether or not that steel plate acquires a permanent magnetization itself depends not only on the strength of the applied field but on the so-called coercivity of the ferromagnetic material, which can vary greatly.
Magnetism is the class of physical attributes that are mediated by a magnetic field, which refers to the capacity to induce attractive and repulsive phenomena in other entities. Electric currents and the magnetic moments of elementary particles giving rise to a magnetic field, which acts on other currents and magnetic moments. Magnetism is one aspect of the combined phenomena of electromagnetism. The most familiar effects occur in ferromagnetic materials, which are strongly attracted by magnetic fields and can be magnetized to become permanent magnets, producing magnetic fields themselves. Demagnetizing a magnet is also possible. Only a few substances are ferromagnetic; the most common ones are iron, cobalt, and nickel and their alloys. The rare-earth metals neodymium and samarium are less common examples. The prefix ferro- refers to iron because permanent magnetism was first observed in lodestone, a form of natural iron ore called magnetite, Fe3O4.
A magnet is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other ferromagnetic materials, such as iron, steel, nickel, cobalt, etc. and attracts or repels other magnets.
In electromagnetism, the magnetic susceptibility is a measure of how much a material will become magnetized in an applied magnetic field. It is the ratio of magnetization M to the applied magnetizing field intensity H. This allows a simple classification, into two categories, of most materials' responses to an applied magnetic field: an alignment with the magnetic field, χ > 0, called paramagnetism, or an alignment against the field, χ < 0, called diamagnetism.
Kurt Wüthrich is a Swiss chemist/biophysicist and Nobel Chemistry laureate, known for developing nuclear magnetic resonance (NMR) methods for studying biological macromolecules.
Ames National Laboratory, formerly Ames Laboratory, is a United States Department of Energy national laboratory located in Ames, Iowa, and affiliated with Iowa State University. It is a top-level national laboratory for research on national security, energy, and the environment. The laboratory conducts research into areas of national concern, including the synthesis and study of new materials, energy resources, high-speed computer design, and environmental cleanup and restoration. It is located on the campus of Iowa State University.
The National High Magnetic Field Laboratory (MagLab) is a facility at Florida State University, the University of Florida, and Los Alamos National Laboratory in New Mexico, that performs magnetic field research in physics, biology, bioengineering, chemistry, geochemistry, biochemistry. It is the only such facility in the US, and is among twelve high magnetic facilities worldwide. The lab is supported by the National Science Foundation and the state of Florida, and works in collaboration with private industry.
Alexander Leonidovich Kuzemsky is a Russian theoretical physicist.
Yevgeny Konstantinovich Zavoisky was a Soviet physicist known for discovery of electron paramagnetic resonance in 1944. He likely observed nuclear magnetic resonance in 1941, well before Felix Bloch and Edward Mills Purcell, but dismissed the results as not reproducible. Zavoisky is also credited with design of luminescence camera for detection of nuclear processes in 1952 and discovery of magneto-acoustic resonance in plasma in 1958.
The term magnetic structure of a material pertains to the ordered arrangement of magnetic spins, typically within an ordered crystallographic lattice. Its study is a branch of solid-state physics.
Allan Roy Mackintosh, FRS was a prominent Danish physicist and a leading authority on magnetism and neutron scattering, especially in the rare-earth metals.
Charles Pence Slichter was an American physicist, best known for his work on nuclear magnetic resonance and superconductivity.
Nuclear magnetic resonance (NMR) is a physical phenomenon in which nuclei in a strong constant magnetic field are perturbed by a weak oscillating magnetic field and respond by producing an electromagnetic signal with a frequency characteristic of the magnetic field at the nucleus. This process occurs near resonance, when the oscillation frequency matches the intrinsic frequency of the nuclei, which depends on the strength of the static magnetic field, the chemical environment, and the magnetic properties of the isotope involved; in practical applications with static magnetic fields up to ca. 20 tesla, the frequency is similar to VHF and UHF television broadcasts (60–1000 MHz). NMR results from specific magnetic properties of certain atomic nuclei. Nuclear magnetic resonance spectroscopy is widely used to determine the structure of organic molecules in solution and study molecular physics and crystals as well as non-crystalline materials. NMR is also routinely used in advanced medical imaging techniques, such as in magnetic resonance imaging (MRI).
Harry Suhl was a German-American physicist who specialized in statistical mechanics, non-equilibrium thermodynamics, and solid-state physics, and in particular superconductivity. Various phenomena in his field of work have been named after him, such as the Suhl instability, Suhl–Nakamura interaction and Abrikosov–Suhl resonance. He died in March 2020 at the age of 97.
Professor Ramakrishna Vijayacharya Hosur is an Indian biophysical scientist, known for his expertise in the areas of nuclear magnetic resonance and molecular biophysics. The Government of India honoured him, in 2014, by awarding him the Padma Shri, the fourth highest civilian award, for his contributions to the fields of science and technology.
Echur Varadadesikan Sampathkumaran is an Indian condensed matter physicist and a Distinguished Professor at the Tata Institute of Fundamental Research. Known for his research on the thermal and transport behaviour of magnetic systems, Sampathkumaran is an elected fellow of all the three major Indian science academies viz. Indian Academy of Sciences, Indian National Science Academy and National Academy of Sciences, India as well as The World Academy of Sciences. The Council of Scientific and Industrial Research, the apex agency of the Government of India for scientific research, awarded him the Shanti Swarup Bhatnagar Prize for Science and Technology, one of the highest Indian science awards, for his contributions to physical sciences in 1999.
Dmitry Dmitriyevich Mishin was a Soviet and Russian physicist, Doctor (habilitate) of physical and mathematical sciences, professor, founder of the scientific school of magnetic scienсе in Tver State University.
Karl Heinz Bennemann is a German condensed matter physicist. He has contributed to the advance on the understanding of traditional BCS and high Tc superconductors, the magnetic properties of alloys, the magnetic properties of low dimensional systems, the physicochemical properties of surfaces, the physicochemical properties of nanostructured materials, ultrafast phenomena, and non-linear optics, among others. His work was recognized through an Alfred P. Sloan fellowship in 1969.
