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arXiv · 0909.0092

Ultranarrow resonance peaks in the transmission and reflection spectra of a photonic crystal cavity with Raman gain

V. G. Arkhipkin·S. A. Myslivets
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Abstract

The Raman gain of a probe light in a three-state $\Lambda $-scheme placed into a defect of a one-dimensional photonic crystal is studied theoretically. We show that there exists a pump intensity range, where the transmission and reflection spectra of the probe field exhibit \textit{simultaneously} occurring narrow peaks (resonances) whose position is determined by the Raman resonance. Transmission and reflection coefficients can be larger than unity at pump intensities of order tens of $\mu$W/cm$^{2}$. When the pump intensity is outside this region, the peak in the transmission spectrum turns into a narrow dip. The nature of narrow resonances is attributed to a drastic dispersion of the nonlinear refractive index in the vicinity of the Raman transition, which leads to a significant reduction of the group velocity of the probe wave.

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V. G. Arkhipkin, S. A. Myslivets. 2009-09-01. Ultranarrow resonance peaks in the transmission and reflection spectra of a photonic crystal cavity with Raman gain. https://doi.org/10.1103/physreva.80.061802

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