A practical approach to calculating magnetic Johnson noise for precision measurements
Magnetic Johnson noise is an important consideration for many applications involving precision magnetometry, and its significance will only increase in the future with improvements in measurement sensitivity. The fluctuation–dissipation theorem can be utilized to derive analytic expressions for magnetic Johnson noise in certain situations, but when used in conjunction with finite element analysis tools, the combined approach is particularly powerful as it provides a practical means to calculate the magnetic Johnson noise arising from conductors of arbitrary geometry and permeability. In this paper, we demonstrate this method to be one of the most comprehensive approaches presently available to calculate thermal magnetic noise. In particular, its applicability is shown to not be limited to cases where the noise is evaluated at a point in space but also can be expanded to include cases where the magnetic field detector has a more general shape, such as a finite-size loop, a gradiometer, or a detector that consists of a polarized atomic species trapped in a volume. Furthermore, some physics insights gained through studies made using this method are discussed.
- Research Organization:
- Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
- Sponsoring Organization:
- USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE Office of Science (SC), Nuclear Physics (NP)
- Grant/Contract Number:
- 89233218CNA000001
- OSTI ID:
- 2475579
- Report Number(s):
- LA-UR--24-27277
- Journal Information:
- Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 12 Vol. 136; ISSN 0021-8979
- Publisher:
- American Institute of Physics (AIP)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Implementation of Johnson Noise Thermometry into Radiation Hardened Electronics
Johnson noise in ideal type-II superconducting films