Incoherent Pair Tunneling as a Probe of the Cuprate Pseudogap
  We argue that incoherent pair tunneling in a cuprate superconductor junction with an optimally doped superconducting and an underdoped normal lead can be used to detect the presence of pairing correlations in the pseudogap phase of the underdoped lead. We estimate that the junction characteristics most suitable for studying the pair tunneling current are close to recently manufactured cuprate tunneling devices. 
Boldizsar Janko, Ioan Kosztin, K. Levin, M. R. Norman, and Douglas J.   Scalapino