Cryogenic sapphire oscillator using a low- vibration design pulse-tube cryocooler: first results

Author

Hartnett, John G. ; Nand, Nitin R. ; Wang, Chao ; Le Floch, J.-M.

Author_Institution

Sch. of Phys., Univ. of Western Australia, Crawley, WA, Australia

Volume

57

Issue

5

fYear

2010

fDate

5/1/2010 12:00:00 AM

Firstpage

1034

Lastpage

1038

Abstract

A cryogenic sapphire oscillator (CSO) has been implemented at 11.2 GHz using a low-vibration design pulse-tube cryocooler. Compared with a state-of-the-art liquid helium cooled CSO in the same laboratory, the square root Allan variance of their combined fractional frequency instability is ??_y = 1.4 ?? 10^-5??^-1/2 for integration times 1 < ?? < 10 s, dominated by white frequency noise. The minimum ??_y = 5.3 ?? 10^-16 for the two oscillators was reached at ?? = 20 s. Assuming equal contributions from both CSOs, the single oscillator phase noise S_?? ?? -96 dB.rad²/Hz at 1 Hz set from the carrier.

Keywords

cryogenic electronics; oscillators; cryogenic sapphire oscillator; fractional frequency instability; frequency 1 Hz; frequency 11.2 GHz; low-vibration design pulse-tube cryocooler; single oscillator phase noise; white frequency noise; Bellows; Copper; Counting circuits; Cryogenics; Frequency measurement; Microwave oscillators; Resonance; Resonant frequency; Temperature control;

fLanguage

English

Journal_Title

Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on

Publisher

ieee

ISSN

0885-3010

Type

jour

DOI

10.1109/TUFFC.2010.1515

Filename

5456252