Spontaneous flux in a d-wave superconductor with time-reversal-symmetry-broken pairing state at (110)-oriented boundaries

The induction of an s-wave component in a d-wave superconductor is considered. Near the (110)-oriented edges of such a sample, the induced s-wave order parameter together with the d-wave component forms a complex combination d+e^iφs, which breaks the time-reversal symmetry (BTRS) of the pairing state. As a result, the spontaneous current is created. We numerically study the current distribution and the formation of the spontaneous flux induced by the current. We show that the spontaneous flux formed from a number of defect lines with (110) orientation has a measurable strength. This result may provide an unambiguous way to check the existence of the BTRS pairing state at (110)-oriented boundaries.