We have performed tunneling measurements on underdoped and optimally doped single crystals of Bi2Sr2CaCu2O8+δ (Bi2212). The tunneling is in the ab-plane, in the maximum gap direction for all of our experiments. Measurement temperature ranges from 4.2 K to well above 100 K. The superconducting gap has been measured for T < Tc. 2Δ/kTc for underdoped Bi2212 (∼13.4) is significantly larger than that of optimally doped Bi2212 (∼8.8). As the temperature is raised above Tc, the gap vanishes for the optimally doped sample. In contrary, the gap like feature for the underdoped Bi2212 persists with larger gap value at higher temperatures. There are interesting differences in the nature of superconducting gap and pseudogap.
|Number of pages||7|
|Journal||International Journal of Modern Physics B|
|State||Published - Dec 20 1998|
ASJC Scopus subject areas
- Statistical and Nonlinear Physics
- Condensed Matter Physics