Orbital Angular Momentum

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Related to Orbital Angular Momentum: spin angular momentum

orbital angular momentum

[′ȯr·bəd·əl ′aŋ·gyə·lər mə′men·təm]
The angular momentum associated with the motion of a particle about an origin, equal to the cross product of the position vector with the linear momentum. Also known as orbital momentum.
(quantum mechanics)
The angular momentum operator associated with the motion of a particle about an origin, equal to the cross product of the position vector with the linear momentum, as opposed to the intrinsic spin angular momentum. Also known as orbital moment.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Orbital Angular Momentum


the angular momentum of a microparticle moving in a strong field that has spherical symmetry. The term “orbital angular momentum” is due to the graphic representation of the motion of an atomic electron in a spherically symmetric field of the nucleus in a definite closed orbit.

According to quantum mechanics, the orbital angular momentum MI is quantized, that is, its value, as well as its projection on an axis arbitrarily selected in space (z-axis), can assume only certain discrete values:

where is Planck’s constant, l = 0, 1, 2, …is the azimuthal (orbital) quantum number, and m = l, l — 1, … , — l is the magnetic quantum number. The classification of the states of microparticles according to the values of l plays a major role in atomic theory, in the theory of the atomic nucleus, and in collision theory.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Dynamically, a larger repulsive orbital angular momentum term in the QCM radial acceleration equation will result in the planets forming at larger orbital equilibrium radii.
Isham, "Orbital angular momentum in radio--A system study," IEEE Trans.
Bergman et al., "Orbital angular momentum in radio--a system study," IEEE Transactions on Antennas and Propagation, vol.
In a renormalizable theory, the change in orbital angular momentum is limited to [DELTA][L.sup.z] = 0, [+ or -] 1 at each vertex [52].
Lavery et al., "High-capacity millimetre-wave communications with orbital angular momentum multiplexing," Nature Communications, vol.
Moreover, we developed [Fe.sup.III] LIESST complexes, phototunable Co-valence tautomeric complexes, and a Co complex exhibiting the change in orbital angular momentum. Furthermore, we extended our work to phototunable clusters and 1-D complexes.
The latter two effects are relativistic and thus quite weak at solar system velocities, but they can nonetheless be significant as they can lead to secular changes in orbital angular momentum and energy.
Moreover, J' = S + L + l, where the electron orbital angular momentum L = I.
In-fact, it is well known that the [[gamma].sup.i]-matrices (i = 1,2,3) represent spin (i.e., [mathematical expression not reproducible]) because, together with the angular momentum operator ([??]), their sum total of the orbital angular momentum and spin [mathematical expression not reproducible] commutes with the Dirac Hamiltonian ([H.sub.D]), i.e.
Zhao, "Probability density of the orbital angular momentum mode of Hankel-Bessel beams in an atmospheric turbulence," Optics Express, vol.
Zeilinger, "Orbital angular momentum of photons and the entanglement of Laguerre-Gaussian modes," Phil.
Vortex beam is a structured light beam that can carry orbital angular momentum (OAM) and possess helical phase-front.