Heat transport across the interface between normal metal and d-wave superconductor

Heat conductance and heat current across normal metal/d-wave superconductor (NID) interface are calculated in the framework of quasiclassical equations. The calculations are performed for different values of boundary transparencies and crystal axis orientation. It is shown that in contrast to N/s-wave boundary the heat conductance of transparent (D=1) NID interface is considerably larger and has a nonactivated form. Electronic heat current across NID structures is also calculated for different interface models taking into account the midgap states and the possibility of generating a gapless s-wave state in the vicinity of rough NID interface. It is shown that NID junctions cannot compete with analogous NIS devices in microrefrigerating and bolometer applications.