Bohr magneton

In atomic physics, the Bohr magneton (symbol μB) is a physical constant and the natural unit for expressing the magnetic moment of an electron caused by its orbital or spin angular momentum. In SI units, the Bohr magneton is defined as and in the Gaussian CGS units as where e is the elementary charge, ħ is the reduced Planck constant, me is the electron mass, c is the speed of light. The idea of elementary magnets is due to Walther Ritz (1907) and Pierre Weiss. Already before the Rutherford model of atomic structure, several theorists commented that the magneton should involve the Planck constant h. By postulating that the ratio of electron kinetic energy to orbital frequency should be equal to h, Richard Gans computed a value that was twice as large as the Bohr magneton in September 1911. At the First Solvay Conference in November that year, Paul Langevin obtained a . Langevin assumed that the attractive force was inversely proportional to distance to the power and specifically The Ștefan Procopiu had obtained the expression for the magnetic moment of the electron in 1911. The value is sometimes referred to as the "Bohr–Procopiu magneton" in Romanian scientific literature. The Weiss magneton was experimentally derived in 1911 as a unit of magnetic moment equal to 1.53e-24 joules per tesla, which is about 20% of the Bohr magneton. In the summer of 1913, the values for the natural units of atomic angular momentum and magnetic moment were obtained by the Danish physicist Niels Bohr as a consequence of his atom model. In 1920, Wolfgang Pauli gave the Bohr magneton its name in an article where he contrasted it with the magneton of the experimentalists which he called the Weiss magneton. A magnetic moment of an electron in an atom is composed of two components. First, the orbital motion of an electron around a nucleus generates a magnetic moment by Ampère's circuital law. Second, the inherent rotation, or spin, of the electron has a spin magnetic moment.

Reading and writing single-atom magnets

Donat Fabian Natterer

The single-atom bit represents the ultimate limit of the classical approach to high-density magnetic storage media. So far, the smallest individually addressable bistable magnetic bits have consisted of 3-12 atoms(1-3). Long magnetic relaxation times have ...

Nature Publishing Group2017

Comparative study between Cubic and Ellipsoidal Fokker-Planck kinetic models

Reading and writing single-atom magnets

Scaling between magnetic field and temperature in the high-temperature superconductor BaFe2(As1−xP x )2

Comparative study between Cubic and Ellipsoidal Fokker-Planck kinetic models

Scaling between magnetic field and temperature in the high-temperature superconductor BaFe2(As1−xP x )2

Reading and writing single-atom magnets