Matter in strong magnetic fields
Abstract
The properties of matter are drastically modified by strong magnetic fields, B>>m2ee3c/ħ3=2.35×109 G (1 G=10-4 T), as are typically found on the surfaces of neutron stars. In such strong magnetic fields, the Coulomb force on an electron acts as a small perturbation compared to the magnetic force. The strong-field condition can also be mimicked in laboratory semiconductors. Because of the strong magnetic confinement of electrons perpendicular to the field, atoms attain a much greater binding energy compared to the zero-field case, and various other bound states become possible, including molecular chains and three-dimensional condensed matter. This article reviews the electronic structure of atoms, molecules, and bulk matter, as well as the thermodynamic properties of dense plasma, in strong magnetic fields, 109 G<<B<~1016 G. The focus is on the basic physical pictures and approximate scaling relations, although various theoretical approaches and numerical results are also discussed. For a neutron star surface composed of light elements such as hydrogen or helium, the outermost layer constitutes a nondegenerate, partially ionized Coulomb plasma if B<~1015 G (at temperature T>~106 K), and may be in the form of a condensed liquid if the magnetic field is stronger (and T >~106 K). For an iron surface, the outermost layer of the neutron star can be in a gaseous or a condensed phase, depending on the cohesive property of the iron condensate.
- Publication:
-
Reviews of Modern Physics
- Pub Date:
- July 2001
- DOI:
- 10.1103/RevModPhys.73.629
- arXiv:
- arXiv:astro-ph/0009333
- Bibcode:
- 2001RvMP...73..629L
- Keywords:
-
- 97.60.Jd;
- 97.10.Ld;
- 01.30.Rr;
- 95.30.Qd;
- 02.60.-x;
- 21.65.+f;
- Neutron stars;
- Magnetic and electric fields;
- polarization of starlight;
- Surveys and tutorial papers;
- resource letters;
- Magnetohydrodynamics and plasmas;
- Numerical approximation and analysis;
- Nuclear matter;
- Astrophysics;
- Condensed Matter;
- Physics - Atomic Physics
- E-Print:
- 45 pages with 9 figures. Many small additions/changes. Accepted for publication in Rev. Mod. Phys