Translator Disclaimer
10 March 2015 Slow light in ruby: delaying energy beyond the input pulse
Author Affiliations +
The mechanism by which light is slowed through ruby has been the subject of great debate. To distinguish between the two main proposed mechanisms, we investigate the problem in the time domain by modulating a laser beam with a chopper to create a clean square wave. By exploring the trailing edge of the pulsed laser beam propagating through ruby, we can determine whether energy is delayed beyond the input pulse. The effects of a time-varying absorber alone cannot delay energy into the trailing edge of the pulse, as a time-varying absorber can only attenuate a coherent pulse. Therefore, our observation of an increase in intensity at the trailing edge of the pulse provides evidence for a complicated model of slow light in ruby that requires more than just pulse reshaping. In addition, investigating the Fourier components of the modulated square wave shows that harmonic components with different frequencies are delayed by different amounts, regardless of the intensity of the component itself. Understanding the difference in delays of the individual Fourier components of the modulated beam reveals the cause of the distortion the pulse undergoes as it propagates through the ruby.
© (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Emma Wisniewski-Barker, Graham Gibson, Sonja Franke-Arnold, Zhimin Shi, Paul Narum, Robert W. Boyd, and Miles J. Padgett "Slow light in ruby: delaying energy beyond the input pulse", Proc. SPIE 9378, Slow Light, Fast Light, and Opto-Atomic Precision Metrology VIII, 93780D (10 March 2015); doi: 10.1117/12.2075912;

Back to Top