Material Specification for Bi:2212; [Bi-Sr-Ca-Cu-O]
Process: Flux Growth
Notes: The authors cite A. Ono, J. Appl. Phys., Vol. 67, L1213 (1988), and summarize the procedure as follows. "Single crystals... were prepared by following the modified flux technique... After mixing appropriate amounts of the constituents, several tablets of the mixture were prepared. These tablets were stacked inside a gold crucile with a hole at the bottom, which was placed inside another gold crucible. The ensemble of these two crucibles was then introduced in an oven, whose temperature was gradually raised to 850 °C over a period of 24 h, and then again to 885 °C in 48 h, at which temperature the samples were maintained for 24 h, then slowly cooled to 500 °C in 72 h."
Formula: Bi2Sr2CaCu2O8+x
Informal Name: Bi:2212
Chemical Family: Bi-Sr-Ca-Cu-O
Chemical Class: Oxide
Structure Type: Single Crystal
Manufacturer: In House
Commercial Name: In House
Production Date:
Lot Number:
Production Form:
Crystallography for Bi:2212; [Bi-Sr-Ca-Cu-O]
| Crystal System: | Tetragonal |
| Formula Units per Cell: | |
| Space Group: | |
Cell Parameters
|
Temp
K
|
a
Å
|
b
Å
|
c
Å
|
| 296 |
3.56 |
-- |
30.73 |
Measurement Method: X-ray diffraction
Cautions: Unevaluated Data
No measurement details were noted.
Critical Temperature for Bi:2212; [Bi-Sr-Ca-Cu-O]
| Critical Temperature (K) |
| 84 |
Measurement Method: Four-probe method
"Four-probe resistivity measurements confirmed... zero resistance at 84 K and below." No additional measurement details were noted.
Cautions: Unevaluated Data
Thermal Expansion for Bi:2212; [Bi-Sr-Ca-Cu-O]
| Temperature (K) |
dα/dT (10-6 K-2) |
Thermal Expansion (10-6 K-1) |
| 80.5 |
-0.12 |
5.30 |
| 84.5 |
-0.07 |
1.19 |
Measurement Method: Capacitance dilatometer
"Thermal expansion of the sample was measured by the use of a high-resolution capacitance dilatometer, potentially capable of detecting length changes as small as 10
-10 m. A variable-temperature cryostat was used to cool the sample. The temperature, measured with a calibrated silicon diode, was allowed to increase at a rate of about 2 mK s
-1 during warming. A General-Ratio 1615 capacitance bridge and an Ithaco lock-in amplifier were used to detect the changes in the length of the samples."
Cautions: Evaluated Data
"An examination of (the thermal expansion data) revealed the occurrence of a jump at about 84 K, indicating a transition temperature of T
c = 84 K."
