Note

Vector network analyzer-ferromagnetic resonance spectrometer using high Q-factor cavity

Chi-Kuen Lo, W. C. Lai, J. C. Cheng

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

A ferromagnetic resonance (FMR) spectrometer whose main components consist of an X-band resonator and a vector network analyzer (VNA) was developed. This spectrometer takes advantage of a high Q-factor (9600) cavity and state-of-the-art VNA. Accordingly, field modulation lock-in technique for signal to noise ratio (SNR) enhancement is no longer necessary, and FMR absorption can therefore be extracted directly. Its derivative for the ascertainment of full width at half maximum height of FMR peak can be found by taking the differentiation of original data. This system was characterized with different thicknesses of permalloy (Py) films and its multilayer, and found that the SNR of 5 nm Py on glass was better than 50, and did not have significant reduction even at low microwave excitation power (-20 dBm), and at low Q-factor (3000). The FMR other than X-band can also be examined in the same manner by using a suitable band cavity within the frequency range of VNA.

Original languageEnglish
Article number086114
JournalReview of Scientific Instruments
Volume82
Issue number8
DOIs
Publication statusPublished - 2011 Aug 1

Fingerprint

Ferromagnetic resonance
Electric network analyzers
ferromagnetic resonance
Spectrometers
Q factors
analyzers
spectrometers
cavities
Permalloys (trademark)
superhigh frequencies
Signal to noise ratio
signal to noise ratios
Full width at half maximum
Resonators
Multilayers
frequency ranges
resonators
Microwaves
Modulation
Derivatives

ASJC Scopus subject areas

  • Instrumentation

Cite this

Note : Vector network analyzer-ferromagnetic resonance spectrometer using high Q-factor cavity. / Lo, Chi-Kuen; Lai, W. C.; Cheng, J. C.

In: Review of Scientific Instruments, Vol. 82, No. 8, 086114, 01.08.2011.

Research output: Contribution to journalArticle

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