Metamagnetism is a physical state of matter characterized by a superlinear increase of magnetization over a narrow range of applied magnetic field. This property actually describes a few distinct magnetic states. An early use of the term (Advances in Physics 26, 487) referred to a field-induced "spin-flip" transition in antiferromagnetic insulators. Later, it was suggested (Philosophical Magazine 7, 1817) that a similar effect would occur in paramagnets on the verge of ferromagnetism, as the result of exchange splitting of the Fermi surface. Depending on the material and experimental conditions, metamagnetism may be associated with a first-order phase transition, a continuous phase transition at a critical point (classical or quantum), or crossovers beyond a critical point that do not involve a phase transition at all. In the physical sciences, a phase is a set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties (i. ... This article needs to be cleaned up to conform to a higher standard of quality. ... Current flowing through a wire produces a magnetic field (M) around the wire. ... In materials that exhibit antiferromagnetism, the spins of magnetic electrons align in a regular pattern with neighboring spins pointing in opposite directions. ... Insulators are materials which prevent the flow of heat (thermal insulators) or electric charge (electrical insulators). ... Paramagnetism is the tendency of the atomic magnetic dipoles, due to quantum-mechanical spin as well as electron orbital angular momentum, to align with an external magnetic field. ... Ferromagnetism is a phenomenon by which a material can exhibit a spontaneous magnetization, and is one of the strongest forms of magnetism. ... In solid-state physics, the Fermi surface is an abstract boundary or interface useful for characterizing and predicting the thermal, electrical, magnetic, and optical properties of metals, semimetals, and semiconductors. ... In physics, a phase transition is the transformation of a thermodynamic system from one phase to another. ... Chemistry In chemistry, a critical point is the conditions ( temperature, pressure) at which the liquid state of the matter ceases to exist. ...