Abstract
External phase locking of a Josephson flux flow oscillator (FFO) to a 10 MHz reference oscillator is demonstrated experimentally in the frequency range 270-440 GHz. A linewidth as low as 1 Hz (as determined by the resolution bandwidth of the spectrum analyser) has been measured. This linewidth is far below the fundamental level given by shot and thermal noise of the free-running tunnel junction. The combination of narrow linewidth, wide band tunability and low noise is important for spectral radio astronomy applications.
Original language | English |
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Journal | Superconductor Science & Technology |
Volume | 12 |
Issue number | 11 |
Pages (from-to) | 720-722 |
ISSN | 0953-2048 |
DOIs | |
Publication status | Published - 1999 |