Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Study of the Excess Noise Associated with Demodulation of Ultra-Short Infrared Pulses

Published

Author(s)

Eugene N. Ivanov, Scott A. Diddams, Leo W. Hollberg

Abstract

The demodulation of ultra-short light pulses with photodetectors is accompanied by excess phase noise at the pulse repetition rate and harmonics in the spectrum of the photocurrent. The major contribution to this noise is power fluctuations of the detected pulse train that, if not compensated for, can seriously limit the stability of frequency transfer from optical to microwave domain. By making use of an infrared femtosecond laser, we measured the spectral density of the excess phase noise, as well as power-to-phase conversion for different types of InGaAs photodetectors. Noise measurements were performed with a novel type of dual-channel readout system using a fiber coupled beam splitter. Strong suppression of the excess phase noise was observed in both channels of the measurement system when the average power of the femtosecond pulse train was stabilized. The results of this study are important for the development of low-noise microwave sources derived from optical ¿clocks¿ and optical frequency synthesis.
Citation
IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control
Volume
52
Issue
7

Citation

Ivanov, E. , Diddams, S. and Hollberg, L. (2005), Study of the Excess Noise Associated with Demodulation of Ultra-Short Infrared Pulses, IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=50268 (Accessed March 28, 2024)
Created June 1, 2005, Updated February 17, 2017