1. High Temperature Superconductivity
In Cuprate Oxide Bi2Sr2Can-1Cu2O2n+4
levitation pic
Google Image Archive
Chelsea Benedict, John DeArmon, Shankar Rananavare,
Portland State University Departments of Chemistry and Physics

2. High Temperature Superconductivity Basics Applications
Experimental Overview
SEM Micrographs
Analysis of XRD
Conclusion: Dependency on Calcium
Bullet point about conclusions/take aways
"Bi 2 Sr 2 Ca Cu 2 O 8." COD Mirror. N.p.: Portland State U, Nanocrystallography Database. Web.

3. HTS Basics: Physical Properties
for all
for all
Common to types I and II
“Flux pinning”
Types of superconductors: pure metals, binary metallic alloys and organic superconductor; cuprate oxides (HTS)

4. Applications
Superconducting electronics, lossless power delivery, and accelerator magnets (1)
NanoSQUIDs (3,5)
Fermilab recently published these images of flexible BSCCO wires for potential use as accelerator magnets.
5: nano superconducting quantum interference devices: “Our aim is the development of NEMS based nanosensors with multi-property metrology capability leading in the longer term to quantum measurement.  Our novel approach is to develop two methods,  The second method is applicable at cryogenic temperatures using a nanoSQUID.”
The National Physical Laboratory in the UK is working on this nanoSQUID limited to <10 K

5. Experimental Overview
Synthesis: -Coprecipitation
method -Calcination
Characterization: -Meissner/Mixed Meissner effect -XRD, SEM/EDX

6. Our Material: BSCCO 2212
BSCCO stoichiometries: 2201, 2212, and BSCCO commonly doped with Pb, and all of these vary Tc. Quote on roughness of diagram p 121: not all sources agree PUT LITTLE INDICATORS FOR EACH SAMPLE
Narlikar, Anant V. The BSCCO System. Huntington, NY: NOVA Science Publ., Print.

7. BSCCO SAMPLE: 500 C ANNEALING BI: 2.4 SR: 1.8 CA: 0.5 CU: 2.3
Size of grains are small, no differentiation
BSCCO SAMPLE: 500 C ANNEALING BI: 2.4 SR: 1.8 CA: 0.5 CU: 2.3

8. Pressed second
FIRST SUCCESSFUL SYNTHESIS BSCCO CRYSTALS, 840 C CALCINATION Bi: 2.2 Sr: 1.6 Ca: 0.5 Cu: 2.7

9. A: Bi2Sr2Ca0Cu1 B: Bi2Sr2Ca1Cu2 C: Bi2Sr2Ca2Cu3 D: (Sr,Ca)14Cu24O41
E F A A B
D E F
F D B C
E F A B D C B
A: Bi2Sr2Ca0Cu1 B: Bi2Sr2Ca1Cu2 C: Bi2Sr2Ca2Cu3 D: (Sr,Ca)14Cu24O41
E: (Sr,Ca)CuO2 F: (Sr,Ca)2CuO3
2201’s Tc is about 20K Takeaway: there is no 2201 phase in this region of the phase diagram

10. Pressed second
FIRST SUCCESSFUL SYNTHESIS BSCCO CRYSTALS, 840 C CALCINATION Bi: 2.2 Sr: 1.6 Ca: 0.5 Cu: 2.7

11. Pressed second. Even if we go to 750 we still get supercondictivity
Pressed second. Even if we go to 750 we still get supercondictivity. Notice the agglomerated cubelike
SUCCESSFUL SAMPLE BSCCO CRYSTALS, 750 C CALCINATION BI: 2.3 SR: 1.7 CA: 0.7 CU: 2.2

12. Clearly early pressing aids in single crystal growth
Clearly early pressing aids in single crystal growth. Pressed immediately
SUCCESSFUL SAMPLE BSCCO CRYSTALS, 840 C CALCINATION BI: 2.7 SR: 2 CA: 0.5 CU: 1.8

13. UNSUCCESSFUL SAMPLE 840 C CALCINATION BI: 2.2 SR: 1.8 CA: .7 CU: 2.2
Strontium rich region of sample 4.1, pressed after calcination
UNSUCCESSFUL SAMPLE 840 C CALCINATION BI: 2.2 SR: 1.8 CA: .7 CU: 2.2

15. Conclusion BSCCO synthesis is very sensitive to processing conditions
Crystal growth and size is dependent upon pressing
Single phase is more dependent on calcium than bismuth

16. Sources
1 Barzi, E., and Al. Et. "BSCCO-2212 Wire and Cable Studies." BSCCO-2212 WIRE AND CABLE STUDIES (2007): n. pag. Workforce Development and Research Section. Fermilab, Web.
2 Cyrot, M., and Davor Pavuna. Introduction to Superconductivity and High-Tc Materials. Singapore: World Scientific, Print.
3 Lieber, Charles M. "One Dimensional Nanostructures: Chemistry, Physics and Applications." Solid State Communications  (1998): Web. 13 Feb
4 Han, Song, Chao Li, Zuqin Liu, Bo Lei, Daihua Zhang, Wu Jin, Xiaolei Liu, Tao Tang, and Chongwu Zhou. "Transition Metal Oxide Core−Shell Nanowires:  Generic Synthesis and Transport Studies." Nano Letters4.7 (2004): Web. 13 Feb
5 "NanoSQUIDs : Research : Quantum Detection : Science + Technology : National Physical Laboratory." National Physical Laboratory. N.p., n.d. Web. 28 Feb
6 "Bi 2 Sr 2 Ca Cu 2 O 8." COD Mirror. N.p.: Portland State U, n.d. N. pag.Nanocrystallography Database. Web.
Thanks to Jacob Reams at PCC for access to the SEM/EDX and to Srikar Rao for access to EDX as well as many others.

17. Next
Develop a higher quality bulk synthesis method -Apply more pressure early in calcination -Try a bismuth-deficient, calcium-rich environment -Investigate the C area of the phase diagram
Develop a method for measuring resistance versus temperature
Move from bulk synthesis to nanowire or thin film synthesis