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Quasi-light Storage for Optical Data Packets
Published on: February 6, 2014
Slowing light down by low magnetic fields: pulse delay by transient spectral hole-burning in ruby
Hans Riesen1, Aleksander K Rebane, Alex Szabo
1School of Physical, Environmental and Mathematical Sciences, The University of New South Wales, UNSW Canberra, Canberra, ACT 2600, Australia. h.riesen@adfa.edu.au
Optics Express
|October 6, 2012
Summary
Scientists observed slow light in pink ruby using spectral hole-burning, controlling pulse delay with a magnetic field. This technique offers potential for new spectroscopic methods.
Area of Science:
- Quantum Optics
- Solid-State Spectroscopy
- Materials Science
Background:
- Slow light phenomena enable control over light propagation speed.
- Transient spectral hole-burning is a technique for modifying material absorption spectra.
- Excited-state population storage is crucial for light manipulation in materials.
Purpose of the Study:
- To demonstrate slow light generation in a solid-state material via transient spectral hole-burning.
- To investigate the influence of external magnetic fields on slow light.
- To explore the potential of this phenomenon for spectroscopic applications.
Main Methods:
- Experiments utilized a 2.3 mm thick pink ruby crystal (Al2O3:Cr(III)).
- The R1-line (2E←4A2 transition) was targeted for spectral hole-burning.
- Low external magnetic fields (B||c≤9 mT) were applied to control pulse delay.
Main Results:
- Slow light with delays up to 11 ns was observed for ~55 ns Gaussian pulses.
- Minimal pulse distortion was achieved.
- A group velocity of approximately c/1400 was measured.
- Experimental results were accurately modeled by linear spectral filter theory.
Conclusions:
- Transient spectral hole-burning in solids can effectively induce slow light.
- External magnetic fields provide a controllable mechanism for pulse delay.
- This method shows promise as a novel spectroscopic technique.
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