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Beta-Detected NQR in Zero Field with a Low Energy Beam of \nuc{8}{Li}$^+$

Z. Salman·R. F. Kiefl·K. H. Chow·W. A. MacFarlane·D. J. Arseneau·S. Daviel·C. D. P. Levy·Y. Maeno·R. Poutissou
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Abstract

Beta-detected nuclear quadrupole resonances (\bnqr) at zero field are observed using a beam of low energy highly polarized radioactive \nuc{8}{Li}$^+$. The resonances were detected in SrTiO$_3$, Al$_2$O$_3$ and Sr$_2$RuO$_4$ single crystals by monitoring the beta-decay anisotropy as a function of a small audio frequency magnetic field. The resonances show clearly that \nuc{8}{Li} occupies one site with non-cubic symmetry in SrTiO$_3, two in Al$_2$O$_3$ and three sites in Sr$_2$RuO$_4$. The resonance amplitude and width are surprisingly large compared to the values expected from transitions between the $|\pm 2> \leftrightarrow |\pm 1>$ spin states, indicating a significant mixing between the $|\pm m>$ quadrupolar split levels.

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Z. Salman, R. F. Kiefl, K. H. Chow, W. A. MacFarlane, D. J. Arseneau, S. Daviel, C. D. P. Levy, Y. Maeno, R. Poutissou. 2005-11-14. Beta-Detected NQR in Zero Field with a Low Energy Beam of \nuc{8}{Li}$^+$. https://doi.org/10.1016/j.physb.2005.11.168

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