| dc.creator |
Coffey, William T. |
|
| dc.creator |
Crothers, D. S. F. |
|
| dc.creator |
Kalmykov, Yuri P. |
|
| dc.creator |
Massawe, Estomih S. |
|
| dc.creator |
Waldron, J. T. |
|
| dc.date |
2016-06-26T16:58:35Z |
|
| dc.date |
2016-06-26T16:58:35Z |
|
| dc.date |
1994 |
|
| dc.date.accessioned |
2018-03-27T08:57:57Z |
|
| dc.date.available |
2018-03-27T08:57:57Z |
|
| dc.identifier |
Coffey, W.T., Crothers, D.S.F., Kalmykov, Y.P., Massawe, E.S. and Waldron, J.T., 1994. Exact analytic formula for the correlation time of a single-domain ferromagnetic particle. Physical Review E, 49(3), p.1869. |
|
| dc.identifier |
http://hdl.handle.net/20.500.11810/2667 |
|
| dc.identifier |
10.1103/PhysRevE.49.1869 |
|
| dc.identifier.uri |
http://hdl.handle.net/20.500.11810/2667 |
|
| dc.description |
Exact solutions for the longitudinal relaxation time T∥ and the complex susceptibility χ∥(ω) of a thermally agitated single-domain ferromagnetic particle are presented for the simple uniaxial potential of the crystalline anisotropy considered by Brown [Phys. Rev. 130, 1677 (1963)]. This is accomplished by expanding the spatial part of the distribution function of magnetic-moment orientations on the unit sphere in the Fokker-Planck equation in Legendre polynomials. This leads to the three-term recurrence relation for the Laplace transform of the decay functions. The recurrence relation may be solved exactly in terms of continued fractions. The zero-frequency limit of the solution yields an analytic formula for T∥ as a series of confluent hypergeometric (Kummer) functions which is easily tabulated for all potential-barrier heights. The asymptotic formula for T∥ of Brown is recovered in the limit of high barriers. On conversion of the exact solution for T∥ to integral form, it is shown using the method of steepest descents that an asymptotic correction to Brown’s high-barrier result is necessary. The inadequacy of the effective-eigenvalue method as applied to the calculation of T∥ is discussed. |
|
| dc.language |
en |
|
| dc.title |
Exact Analytic Formula for the Correlation Time of a Single-Domain Ferromagnetic Particle |
|
| dc.type |
Journal Article, Peer Reviewed |
|