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arXiv · 0911.4947

Spectroscopic investigations of a Ti:Tm:LiNbO3 waveguide for photon-echo quantum memory

N. Sinclair·E. Saglamyurek·M. George·R. Ricken·C. La Mela·W. Sohler·W. Tittel
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Abstract

We report the fabrication and characterization of a Ti$^{4+}$:Tm$^{3+}$:LiNbO$_3$ optical waveguide in view of photon-echo quantum memory applications. In particular, we investigated room- and cryogenic-temperature properties via absorption, spectral hole burning, photon echo, and Stark spectroscopy. We found radiative lifetimes of 82 $\mu$s and 2.4 ms for the $^3$H$_4$ and $^3$F$_4$ levels, respectively, and a 44% branching ratio from the $^3$H$_{4}$ to the $^3$F$_4$ level. We also measured an optical coherence time of 1.6 $\mu$s for the $^3$H$_6\leftrightarrow{}^3$H$_4$, 795 nm wavelength transition, and investigated the limitation of spectral diffusion to spectral hole burning. Upon application of magnetic fields of a few hundred Gauss, we observed persistent spectral holes with lifetimes up to seconds. Furthermore, we measured a linear Stark shift of 25 kHz$\cdot$cm/V. Our results are promising for integrated, electro-optical, waveguide quantum memory for photons.

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N. Sinclair, E. Saglamyurek, M. George, R. Ricken, C. La Mela, W. Sohler, W. Tittel. 2009-11-25. Spectroscopic investigations of a Ti:Tm:LiNbO3 waveguide for photon-echo quantum memory. https://doi.org/10.1016/j.jlumin.2009.12.022

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