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Updated: May 13, 2026

Rejection of Fluorescence Background in Resonance and Spontaneous Raman Microspectroscopy
Published on: May 18, 2011
Time reversal of optically carried radiofrequency signals in the microsecond range
H Linget1, L Morvan, J-L Le Gouët
1Laboratoire Aimé Cotton, CNRS-UPR 3321, Orsay 91405, France. heloise.linget@u‑psud.fr
Abstract:
The time-reversal (TR) protocol we implement in an erbium-doped YSO crystal is based on photon echoes but avoids the storage of the signal to be processed. Unlike other approaches implying digitizing or highly dispersive optical fibers, the proposed scheme reaches the μs range and potentially offers high bandwidth, both required for RADAR applications. In this Letter, we demonstrate faithful reversal of arbitrary pulse sequences with 6 μs duration and 10 MHz bandwidth. To the best of our knowledge, this is the first demonstration of TR via linear filtering in a programmable material.
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