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[en] We have studied the physics of atoms with permanent electric dipole moment and nonvanishing magnetic moment interacting with an electric field and inhomogeneous magnetic field. This system can be demonstrated as the atomic analogue of Landau quantization of charged particles in a uniform magnetic field. This Landau-like atomic problem is also studied with space-space noncommutative coordinates
[en] Measurements of nuclear magnetic dipole and electric quadrupole moments are considered quite important for the understanding of nuclear structure both near and far from the valley of stability. The recent advent of radioactive beams has resulted in a plethora of new, continuously flowing, experimental data on nuclear structure – including nuclear moments – which hinders the information management. A new, dedicated, public and user friendly online database ( (http://magneticmoments.info)) has been created comprising experimental data of nuclear electromagnetic moments. The present database supersedes existing printed compilations, including also non-evaluated series of data and relevant meta-data, while putting strong emphasis on bimonthly updates. The scope, features and extensions of the database are reported.
[en] Pfirsch [Z. Naturforsch., Teil A 39, 1 (1984)] has shown that the charge and current density in the guiding-center representation have contributions from electric dipole moments and magnetic dipole corrections. These moments are interpreted in terms of elementary guiding-center theory, and their role in the expression for the total momentum density is explained
[en] The origin of matter is one of the deepest questions addressed by science and remains a mystery because our understanding of the Big Bang suggests that equal amounts of matter as antimatter would be created and annihilate leaving nothing from which stars, galaxies, planets and ultimately life as we know it was created. We know this is not the case in the universe, and so the explanation that the laws of physics can distinguish the difference of moving forward and backward in time and provide mechanisms that produce more matter that antimatter so that a little bit was left over. These same laws of physics affect our world today and would very slightly change the shape of an atom, stretching is along the direction of the spin of its nucleus. This subtle shape change has been searched in many systems - the neutron, atoms and molecules, but has not yet been detected, even as the motivation is strengthened by our understanding of their structure. We therefore look to new systems that have special features that make these effects stand out. Rare isotopes provide one possibility and specific radon atoms are our choice. We have developed techniques to make these measurements with short-lived radioactive atoms, studied the nuclei to provide deeper understanding of how these affect arise in such atoms (including radium) and developed new laser-based techniques to measure and control the magnetic fields necessary to perform these exquisitely sensitive measurements. In this work we have shown that radioactive radon atoms can be produced and transported to an apparatus that lines up the spins of the atoms. We have also shown that the nuclei of nearby radium are pear shaped and that the radon nuclei likely oscillate from one pear shape to its mirror reflection. We have also used the techniques which control nuclear spin to study the magnetic environment in a magnetically shielded room, which has the smallest magnetic field in a large volume in the universe. Measuring magnetic fields and detecting noble atoms' shapes using lasers will provide new techniques for these measurements and impact a broad range of applications including measurements of the neutron EDM. Harvesting rare isotopes at the future FRIB facility at Michigan State University will provide much stronger sources of the isotopes of radon and radium for future-generation experiments and also provide new isotopes for applications including medicine.
[en] The most recent tabulations of nuclear magnetic dipole and electric quadrupole moments have been prepared and published by the Nuclear Data Section of the IAEA, Vienna [N. J. Stone, Report No. INDC(NDS)-0650 (2013); Report No. INDC(NDS)-0658 (2014)]. The first of these is a table of recommended quadrupole moments for all isotopes in which all experimental results are made consistent with a limited number of adopted standards for each element; the second is a combined listing of all measurements of both moments. Both tables cover all isotopes and energy levels. In this paper, the considerations relevant to the preparation of both tables are described, together with observations as to the importance and (where appropriate) application of necessary corrections to achieve the “best” values. Some discussion of experimental methods is included with emphasis on their precision. The aim of the published quadrupole moment table is to provide a standard reference in which the value given for each moment is the best available and for which full provenance is given. A table of recommended magnetic dipole moments is in preparation, with the same objective in view
[en] A charged body in an elliptic Keplerian orbit in a central gravitational field and dipolar magnetic field is considered. It is assumed that the magnetic dipole is at the center of gravity and rotates about the axis which passes through its center, but in general doesn't coincide with the dipol's axis of symmetry. The principal moment of Lorentz forses acting on the body which moves in the magnetic field is determined. 1 ref
[en] We study the quantum dynamics of a neutral particle that possesses a permanent magnetic and electric dipole moments in the presence of an electromagnetic field. The analysis of this dynamics demonstrates the appearance of a quantum phase that combines the Aharonov-Casher effect and the He-Mckellar-Wilkens effect. We demonstrate that this phase is a special case of the geometric quantum phase. A series of field configurations where this phase would be found is presented. A generalized Casella-type effect is found in one of these configurations. A physical scenario for the quantum phase in an interferometric experiment is proposed
[en] Heteronuclear molecules have attracted wide attention due to their permanent electric dipole moments. Analogous to atoms with magnetic dipoles, the existence of nonzero electric dipoles significantly enhances the possibilities and mechanisms for the control and design of quantum degenerate molecule systems with electric (E) fields. This work proposes a vortex creation mechanism inside a condensate of heteronuclear molecules through the adiabatic flipping of the axial bias of an analogous E-field Ioffe-Pritchard trap (IPT), extending the original protocol of Isoshima et al (2000 Phys. Rev. A 61 063610) for an atomic spinor condensate inside a magnetic (B)-field IPT. We provide both analytic proof and numerical simulations to illustrate the high fidelity operation of this vortex pump protocol. We hope our work provides stimulating experimental possibilities for active investigations in quantum degenerate molecule systems.
[en] Transformation of the relativistic electromagnetic dipole moment is discussed. This quantity is set by an antisymmetric 4-tensor of rank 2, the time components of which define magnetic moment and the spatial ones - relativistic electric dipole moment. It is emphasized that experimental fact of absence of own electric dipole moment of elementary particle (when the magnetic moment is present) leads to definite condition for time coordinates of particle constituents - quarks. 7 refs
[en] The ratchet effect is demonstrated theoretically for the simple model of a vortex in a thin superconducting film interacting with a periodic array of magnetic dipoles placed in the vicinity of the film . The pinning potential for the vortex is calculated in the London limit and found to break spatial inversion symmetry and to depend on the orientation of the magnetic dipole moments. The motion of the vortex at zero temperature driven by a force oscillating periodically in time is investigated numerically. Drift vortex motion consisting of displacements by a translation vector of the dipole array during each period of oscillation is obtained and studied in detail. The direction of drift differs in general from that of the driving force, except if the driving force oscillates in a direction of high symmetry of the dipole array. The vortex drift velocity depends on the orientation of the magnetic moments, and can be tuned by rotating the dipoles. It is pointed out that if the magnetic moments are free to rotate, the ratchet effect can be produced and tuned by a magnetic field applied parallel to the film surfaces