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arXiv · 1007.3579

On the possible secondary component of the order parameter observed in London penetration depth measurements

Angelo Valli·Giorgio Sangiovanni·Massimo Capone·Carlo Di Castro
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Abstract

We discuss the effect of a secondary component of the superconducting order parameter on the superfluid density in the cuprates. If we assume a main $d_{x^2-y^2}$ gap, the most stable realization of a mixed order parameter has a time-reversal breaking $d_{x^2-y^2}+ \imath d_{xy}$ symmetry. In this state the nodes are removed and the temperature dependence of the superfluid density changes from the linear behavior of a pure d-wave to a more rounded shape at low temperature. The latter is compatible with the behavior experimentally observed in the in-plane magnetic field penetration depth of optimally doped $La_{2-x}Sr_xCuO_2$ and $YBa_2Cu_3O_{7-δ}$.

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Angelo Valli, Giorgio Sangiovanni, Massimo Capone, Carlo Di Castro. 2010-07-21. On the possible secondary component of the order parameter observed in London penetration depth measurements. https://doi.org/10.1103/physrevb.82.132504

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