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

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.

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)

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

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

Our Material: BSCCO 2212 BSCCO stoichiometries: 2201, 2212, and 2223. 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., 2001. Print.

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

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

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 http://www.me.utexas.edu/~ferreira/publications/papers/superconductor132000.pdf Takeaway: there is no 2201 phase in this region of the phase diagram

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

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

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

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

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

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, 2007. Web. 2 Cyrot, M., and Davor Pavuna. Introduction to Superconductivity and High-Tc Materials. Singapore: World Scientific, 1992. Print. 3 Lieber, Charles M. "One Dimensional Nanostructures: Chemistry, Physics and Applications." Solid State Communications 170.11 (1998): 607-16. Web. 13 Feb. 2015. 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): 1241-246. Web. 13 Feb. 2015. 5 "NanoSQUIDs : Research : Quantum Detection : Science + Technology : National Physical Laboratory." National Physical Laboratory. N.p., n.d. Web. 28 Feb. 2015. 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.

Next Develop a higher quality bulk synthesis method -Apply more pressure early in calcination -Try a bismuth-deficient, calcium-rich environment -Investigate the 700-800 C area of the phase diagram Develop a method for measuring resistance versus temperature Move from bulk synthesis to nanowire or thin film synthesis