Determination of the Microwave Field Strength Using the Rabi Oscillation for a New Microwave Power Standard

Autor: Moto Kinoshita, K. Komiyama, Kazuhiro Shimaoka
Rok vydání: 2009
Předmět:
Zdroj: IEEE Transactions on Instrumentation and Measurement. 58:1114-1119
ISSN: 1557-9662
0018-9456
DOI: 10.1109/tim.2008.2010677
Popis: This paper describes the development of a new type of microwave power standard based on atomic resonances. An atomic Rabi frequency is proportional to the magnetic field strength of the resonant microwave; the proportionality constant is determined only from fundamental constants and atomic quantum theory. The microwave field strength that corresponds to microwave power is thus uniquely determined by the Rabi frequency. The proportionality constant can thus serve as the basis for a new microwave power standard. This paper confirmed that the Rabi frequency of cesium-133 (133Cs) atoms in a rectangular cell is proportional to the incident microwave field strength. A rectangular Cs glass cell was developed and inserted into a WR90 waveguide-an industrially practical waveguide that permits the impedance analysis necessary to measure microwave power. The microwave field strength in the Cs cell can be adjusted to arbitrary values proportional to the Rabi frequency. The relative expanded uncertainties of the effective microwave magnetic field strength H eff for the coverage factor k = 2, which is typically less than 7%, averaged 4%. The dynamic range of the available Rabi frequency was 31.9 dB.
Databáze: OpenAIRE