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Updated: Jun 20, 2026
15:58
Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing
Published on: December 3, 2013
Propagation of spatial coherence in fast pulses
Robert W Schoonover1, Brynmor J Davis, Randy A Bartels
1Department of Electrical and Computer Engineering and The Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, 405 N. Mathews, Urbana, Illinois 61801, USA. rschoono@illinois.edu
Summary
Analyzing partially correlated fast pulses in diffraction and interferometry reveals that averaged data, not single shots, are crucial for inferring source properties. This extends previous work on temporal correlations in Young
Area of Science:
- Optics and Photonics
- Quantum Optics
- Wave Phenomena
Background:
- Previous studies on pulsed field interferometry primarily focused on temporal correlations.
- Young's interferometer experiments typically assume fully correlated fields.
Purpose of the Study:
- To generalize diffraction and interferometry analysis for partially correlated pulsed fields in both time and space.
- To investigate the interpretation of interferograms across different measurement zones (near, Fresnel, far).
Main Methods:
- Theoretical analysis of diffraction and interferometry for partially correlated fields.
- Extension of previous work on temporal correlations to include spatial correlations.
- Examination of interferogram meaning in various spatial zones.
Main Results:
- The analysis is extended to include both temporal and spatial correlations of pulsed fields.
- The interpretation of interferograms is clarified for near, Fresnel, and far zones.
- It is demonstrated that single-shot measurements are insufficient for determining source statistical properties.
Conclusions:
- Averaging data over multiple pulses is necessary for accurate inference of source statistical properties.
- The study provides a more comprehensive framework for understanding interferometry with partially correlated fields.
- Findings are relevant for advanced optical measurements and characterization of light sources.
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