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Overview and Application of Superconducting Materials. CHEN 313: Materials Group 11 Raul Calzada Chris Gibson Tasnim Mohamed Patty Soong. http://ocw.mit.edu/ans7870/8/8.02T/f04/visualizations/faraday/16-superconductor/16-12_wmv320.html. Papers Used: - PowerPoint PPT Presentation
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Overview and Application of Superconducting Materials
CHEN 313: MaterialsGroup 11
Raul CalzadaChris Gibson
Tasnim MohamedPatty Soong
Papers Used:• Overview of Superconductivity and Challenges in Applications• Entangling Superconductivity and Antiferromagnetism• Review on Superconductivity: The Phenomenon Occurred at Low Temperature• 100 Years of Superconductivity and 50 Years of Superconducting Magnets• Superconductors Beyond 1-2-3• Superconducting Properties of Ag and Sb Substitution on Low-Density YBa2Cu3Ox Superconductor• Fundamentals of Materials Science and Engineering: Magnetic Properties
http://ocw.mit.edu/ans7870/8/8.02T/f04/visualizations/faraday/16-superconductor/16-12_wmv320.html
Graphical Abstract
Callister, W.D. 2012, 776-779.
http://lrrpublic.cli.det.nsw.edu.au/lrrSecure/Sites/Web/physics_explorer/physics/lo/superc_05/superc_05_02.htm Cava, J.R. Sci. Amer. 1990.
http://www.magnet.fsu.edu/education/tutorials/magnetacademy/mri/
http://science.nasa.gov/science-news/science-at-nasa/2003/05feb_superconductor/
http://science.nasa.gov/science-news/science-at-nasa/2003/05feb_superconductor/
http://en.wikipedia.org/wiki/Meissner_effect
Electromagnetic
PracticalStru
ctur
e
State
Superconducting materials have electromagentic properties, a unique structure, are in a special state of matter, and will have practical applications in the future
History of Superconductivity• Helium liquefier completed in 1908 in
Leiden
• Superconductivity first observed in 1911 by Kamerlingh Onnes
• Meissner effect discovered in 1933
• First superconducting magnet made in 1954 by George Ynetma
• Yttrium Barium Copper Oxide superconductor with a transition temperature of 90 K developed in 1987 Figure 3.1: Kamerlingh Onnes
(left) and Van der Waals (right) with the Leiden helium liquefier.
https://commons.wikimedia.org/wiki/File:Heike_Kamerlingh_Onnes_and_Johannes_Diderik_van_der_Waals.jpg
Figure 3.2: Walther Meissner, the discoverer of damping of the magnetic field in superconductors (Meissner effect)
http://en.wikipedia.org/wiki/Walther_Meissner
Callister, W.D. 2012, 776-779Wilson, N.W.; IEEE Trans. Appl. Supercond. 2012, 22, 3.
Introduction
Superconductivity• Superconductivity is a state of thermodynamical equilibrium that
affects a material's electric and magnetic properties.
• Superconductivity arises from an attractive interaction between pairs of conducting electrons, and their interaction with lattice vibrations*
• It can be achieved by lowering the material temperature below its critical temperature
*The advanced theory behind superconductivity is beyond the scope of the presentation
http://hyperphysics.phy-astr.gsu.edu/hbase/solids/coop.html
http://wikis.lib.ncsu.edu/index.php/Magnetic_Levitation_with_Superconductors Flukiger, R. Rev. Accel. Sci. Tech. 2012, 5, 1-23.
Figure 4.2: Cooper pair illustrating energy exchange through phonon interaction.
Figure 4.1: Illustration of cooper pairs moving through a lattice. Cooper pair movement is thought to be the reason superconductivity occurs.
Antiferromagnetism and Theory• In 1957, Bardeen, Cooper, and Schrieffer (BCS) theorized that
superconductivity was the result of electrons binding to form particles called Cooper pairs
• The electrons exchange vibrational lattice energy called phonons which can result in the electrons becoming attracted to one another
• Recently, antiferromagnetism has been linked to the explanation of high temperature ceramic superconductivity
• By changing the chemical composition, BaFe2(As1-xPx)2 has been observed to have an internal magnetic critical point
• As the composition is changed, antiferromagnetism decreases until it disappears, resulting in superconductivity
Figure 5.1: (Top) Lattice of an antiferromagnet. The electron spins are antiparallel, leading to cancellation of the magnetic field. (Bottom) Cooper pair formation. Electrons bind during superconductivity and create boson particles called Cooper pairs. Sachdev, S. Science. 2012, 336, 1510-1511.
Sachdev, S. Science. 2012, 336, 1510-1511.
Basic Principles
Electricity:Properties of Superconductors
• Below a critical temperature (Tc), the resistance of a superconducting material becomes almost zero causing current to flow indefinitely and with no power loss
• No voltage difference is needed to maintain a current.
• Above a current density, superconductivity is lost in the material.
• A supercurrent can flow across an insulating junction in what is called the Josephson Effect. Cooper pairs can do this due to quantum tunneling
Figure 6.1: Critical temperature, current density, and magnetic field boundary separating superconducting and normal conducting states. Superconductivity can only occur within the teardrop figure.
http://hyperphysics.phy-astr.gsu.edu/hbase/solids/squid.html
Callister, W.D. 2012, 776-779.
Flukiger, R. Rev. Accel. Sci. Tech. 2012, 5, 1-23.Patel, M.J. et. al. Nat. Confer. Rec. Trend. Engr. Tech. 2011.Sachdev, S. Science. 2012, 336, 1510-1511
Figure 6.2: Schematic of the Josephson Effect; this effect allows electrons to jump through insulators
Magnetism:Properties of Superconductors
Superconductors can be classified into two types according to their interaction with an external magnetic field:
Type I
• Type I superconductors expel all magnetic flux
• Superconductivity ends when a
critical flux is applied. Examples include mercury, lead, and tin. http://www.gitam.edu/eresource/Engg_Phys/semester_2/supercon/type_1_2.ht
m
Callister, W.D. 2012, 776-779.Patel, M.J. et. al. Nat. Confer. Rec. Trend. Engr. Tech. 2011.
Figure 7.1: Type I superconductors are different than Type II superconductors. This figure shows the comparison of graphs Bc vs Tc in both types. Type II has a mixed state while Type I does not.
Magnetism:Properties of Superconductors
Type II
• Type II superconductors, unlike type I, have two critical fields.
• After the first critical field is reached, magnetic flux partially penetrates the material and it enters a state of mixed normal and superconductivity.
• After the second critical flux is passed, superconductivity abruptly ends. Type II superconductors usually have higher critical temperatures.
• Examples include YBCO, vanadium, and BSCCO
http://es.wikipedia.org/wiki/Superconductor_de_tipo_II
Figure 8.1: Graph illustrating magnetization versus magnetic field strength. Type I is red and Type II is blue. If an external magnetic field is applied, Type II's field gradually declines while Type I has a sharp drop off. This demonstrates a significant difference between the types.Callister, W.D. 2012, 776-779.
Patel, M.J. et. al. Nat. Confer. Rec. Trend. Engr. Tech. 2011.
Fig 9.1: Comparison of superconductor and standard conductor in a magnetic field. The superconductor excludes itself from the field while the field passes through the conductor.
Superconductor Conductor• The phenomena of expelling magnetic flux
experienced by superconductors is called the Meissner Effect.
• The Meissner Effect can be understood as perfect diamagnetism, where the magnetic moment of the material cancels the external field or M = - H.
• The critical field and temperature are interdependent through:
Bc= B0[1-(T/Tc)2 ]
This is observed in Type I superconductors, but it can also be used to approximate the behavior of Type II
Magnetism:Properties of Superconductors
Callister, W.D. 2012, 776-779.Flukiger, R. Rev. Accel. Sci. Tech. 2012, 5, 1-23.Patel, M.J. et. al. Nat. Confer. Rec. Trend. Engr. Tech. 2011.
Callister, W.D. 2012, 776-779.
• The strange magnetic properties created by superconductors can cause the material to levitate in place over a magnet
• The superconductor will remain a certain distance from the magnet but will not flip over or reorient
• This video demonstrates this phenomena and potential for levitation applications
http://www.youtube.com/watch?v=6lmtbLu5nxw
Magnetism:Properties of Superconductors
Superconducting MaterialsTable 11.1: Critical Temperatures of Conducting Materials• In most metals such as titanium,
copper, or lead, resistivity decreases as temperature decreases
• However, the resistivity suddenly drops to near zero at a critical temperature (Tc)
• Metals and metal alloys have a critical temperature of less than about 20 K, which is extremely low and difficult to achieve.
• Yttrium Barium Copper Oxide (YBCO) has a critical temperature of 92 K and others are even higher. These temperatures can be achieved by utilizing liquid nitrogen, a relatively cheap coolant.
Figure adapted from
Callister, W.D. 2012, 776-779.
Material Critical Temperature Critical Magnetic Flux Tc (K) Bc (tesla)
Metals• Some metals become superconductors at
extremely low temperatures
• Some of these include mercury, lead, tin, aluminum, lead, niobium, cadmium, gallium, zinc, and zirconium
• Unfortunately, the critical temperatures are too low for practical application
• For example, Aluminum has a Tc of only 1.20K, nearly impossible to reach by conventional methods
Fig. 12.1: Aluminum tubing can become superconductive at very low temperatures.http://www.globalmetals.com/aluminum-tubestubing.html
Fig. 12.2: Lead can also become superconductive at low temperatures.http://39clues.wikia.com/wiki/Lead
Patel, M.J. et. al. Nat. Confer. Rec. Trend. Engr. Tech. 2011.
Metal Alloys
• Metal alloys like Nb-Ti, and Nb-Zr are usually Type II superconductors
• Metal Alloys have higher critical temperatures and magnetic fluxes than pure metals.
• As a consequence of their properties, they are more useful for practical applications than pure metals
http://www.intechopen.com/books/applications-of-high-tc-superconductivity/superhard-superconductive-composite-materials-obtained-by-high-pressure-high-temperature-sintering
Patel, M.J. et. al. Nat. Confer. Rec. Trend. Engr. Tech. 2011.
Fig 13.1: Lattice structure of Nb-Ti metal alloy. The different composition allows the Tc to be higher than metals.
High Tc Ceramics• Yttrium Barium Copper Oxide was the first
superconductor developed with a Tc above the boiling point of Nitrogen (Tc=90 K).
• Thallium Barium Calcium Copper Oxide has the highest Tc out of all superconductors (Tc=125 K)
• Copper Oxides are believed to be good superconductors partly due to the Jahn-Teller effect, which causes the 2 oxygens on opposite sites of the octahedron to be farther from the copper than the other 4 oxygens of the octahedron.
• This suggests that the electrons interact strongly with the positions of copper and oxygen in the lattice (Cooper pair).
• Antiferromagnetism must be eliminated for superconductivity to appear.
CopperIronhttp://www.chemistryexplained.com/St-Te/Superconductors.html
Cava, J.R. Sci. Amer. 1990.
Cava, J.R. Sci. Amer. 1990.
Figure 14.1 (top): Illustration of a ceramic lattice. The Jahn-Teller effect causes the superconductivity here. Figure 14.2 (bottom): Levitation caused by the interactions of electrons and oxygen, and therefore superconductivity.
High Tc Ceramics continued
Fig 15.1: Other copper oxides that are also superconducting. These ceramics show potential for applications. For industrial setting, the toxicity of the materials should be considered. Cava, J.R. Sci. Amer. 1990.
High Tc Ceramics continued
Figure 16.1: As time continues, superconductors with higher Tc values are being developed and discovered. The trend moves upward. Flukiger, R. Rev. Accel. Sci. Tech. 2012, 5, 1-23. (modified)
Work Performed: Superconducting Properties of Ag and Sb Substitution on Low-Density YBa2Cu3Oδ
• Different concentrations of Silver (Ag) and Lead (Sb) were introduced as impurities into a YBCO ceramic compound
• It was found that the addition of Ag at an optimum concentration enhanced both the critical temperature and current density of YBCO. Above and below this concentration the properties diminished
• Sb impurities did not affect the superconducting properties of the YBCO ceramic.
• As impurities of Ag and Pb were added to YBCO, the transition temperature range, delta Tc was affected
• The correlation between concentration of Ag or Pb versus transition temperature difference appeared to be random
Azhan, F.; et al. J. Supercond. Nov. Magn. 2013, 26, 921-935.
http://www.kreynet.de/asc/ybco.html
Silver (Ag)
Lead (Pb)
http://www.galleries.com/Lead
http://www.hobart.k12.in.us/ksms/PeriodicTable/antimony.htm
Figure 17.1: Adding Ag and Pb impurities to the lattice structure of YBCO can alter its superconductive properties slightly.
Work Performed continued
Azhan, F.; et al. J. Supercond. Nov. Magn. 2013, 26, 921-935.
Fig 18.1: The onset temperature is the upper range of the transition range. The zero temperature is the lower range. The table shows the varying effect of adding impurities in the YBCO on the transition temperature range.
Our Assessment of the Work
Azhan, F.; et al. J. Supercond. Nov. Magn. 2013, 26, 921-935.
• From the work, the transition temperature range of YBCO can be controlled using impurities of metals
• This experiment was useful because it shows that adding impurities to YBCO can alter its Tc and Jc values slightly
• This may be helpful for figuring out new ceramic superconductors. For example, another experiment could be adding gold or platinum impurities to YBCO to see its effect on its superconductive properties
• This experiment will also help elucidate the molecular working of superconducting materials by showing different crystals structures were superconduction occurs.
http://commons.wikimedia.org/wiki/File:YBCO-3D-balls.png
Figure 19.1: Lattice structure of YBCO showing its complexity. In this experiment, YBCO was modified to test its properties.
Our Assessment of Superconductors• Superconductors have potential to create a new
variety of electrical and magnetic technologies
• Superconductors will need to be improved by researching and synthesizing a ceramic superconductor with a high critical temperature value
• By doing this, either minimum cooling, or no cooling at all would be needed to create superconductive properties in the material
• For example, YBCO only requires liquid nitrogen for cooling. Conventional freezers could be used if the Tc could be increased to around 190 K
• Since superconductors can be applied without solid understanding of the theory behind it, they are an attractive materialHgBa2Ca2Cu3Ox
Figure 20.1: Applied Magnetic Field vs Critical Temperature. As the critical temperature increases, the applied magnetic field decreases.
http://www.imagesco.com/articles/superconductors/determining-critical-magnetic-field.html (modified)
Flukiger, R. Rev. Accel. Sci. Tech. 2012, 5, 1-23.Patel, M.J. et. al. Nat. Confer. Rec. Trend. Engr. Tech. 2011.
Further Research Suggestions:Electrical
• If a high critical temperature superconductor is developed that has a critical temperature that is higher than HBCCO (133 K), more practical applications will become feasible
• Electrical power transmission through superconducting materials and wire o Low power losso Low voltage required for high currento Utilizes less physical space
• Computer signal transmission o Low resistivity allows for computing
speed to increase greatly
http://gigaom.com/2010/10/06/superconducting-wire-powering-up-korean-smart-grid/
http://nextbigfuture.com/2009/12/cost-and-benefits-of-2g-superconducting.html
Callister, W.D. 2012, 776-779.Flukiger, R. Rev. Accel. Sci. Tech. 2012, 5, 1-23.
Figure 21.1,2: Power lines demonstrating the great reduction of space needed by utilizing superconducting wire rather than standard cables.
Further Research Suggestions:Electrical
http://gigaom.com/2010/10/06/superconducting-wire-powering-up-korean-smart-grid/
Figure 22.1: Example of a superconducting cable. The liquid nitrogen coolant is part of the cable in order to keep the superconductor wire below the critical temperature. These cables can greatly reduce the physical space needed in our electrical infrastructure.
Callister, W.D. 2012, 776-779.Flukiger, R. Rev. Accel. Sci. Tech. 2012, 5, 1-23.
Further Research Suggestions:Magnetic
• Some applications are used today:o Magnetic Resonance Imagingo Nuclear Magnetic Resonance
Spectroscopy
• Future applications can benefit from interesting magnetic properties displayed by superconductors
• Particle Accelerators
• Magnetic Levitation o High-Speed Magnetic Levitation
Trains for mass transport o By utilizing levitation, friction
between the train and the track is eliminated
o This can allow trains to increase their speed dramatically
http://science.nasa.gov/science-news/science-at-nasa/2003/05feb_superconductor/ http://www.cis.rit.edu/class/schp730/lect/lect-17.htm
http://www.magnet.fsu.edu/education/tutorials/magnetacademy/mri/fullarticle.html
Callister, W.D. 2012, 776-779.Flukiger, R. Rev. Accel. Sci. Tech. 2012, 5, 1-23.Patel, M.J. et. al. Nat. Confer. Rec. Trend. Engr. Tech. 2011.
Figure 23.1,2 (top/middle): MRI scanners currently utilize superconductors.Figure 23.3 (bottom): Mag-Lev train demonstrating the potential of using superconductors in mass-transport.
Conclusions• Superconductivity is a state of thermodynamical equilibrium
where the electrical resistance is 0 and that is achieved at near 0 K temperatures
• External magnetic flux is expelled from the superconductor in what is called the Meissner effect. The application of an external magnetic flux also lowers the critical temperature at which superconductivity is achieved. After a critical flux, superconductivity can no longer be achieved
• Using superconducting materials in circuit elements would mean zero power loss due to resistance. Also, no voltage difference would be needed to maintain the current.
• Adding impurities to ceramic superconductors can alter the critical temperature and critical current density
• Superconducting ceramic materials have shown the most promise for future technologies because of their relatively high critical temperatures
• The underlying principles of superconductivity are explained through an interactive attraction between electrons (Cooper pair) and their interaction with lattice vibrations (phonons).
Figure 24.1: Structural interpretation of a ceramic superconductor. Notice how there are layers of molecules sandwiched between others.
http://physics.aps.org/story/v9/st12
ReferencesAzhan, F.; Fariesha, F.; Yusainee, S. Y. S.; Azman, K.; Khalida, S.; Superconducting Properties of Ag
and Sb Substitution on Low-Density YBa2Cu3Oδ Superconductor. J Supercond Nov Magn. 2013, 26, 921-935.
Callister, W.D.; Rethwisch, D.G. Fundamentals of Materials Science and Engineering. John Wiley & Sons, Inc. 2012, Magnetic Properties, p776-779.
Cava, J.R.; Superconductors and beyond 1-2-3. Scientific American 1990.
Flukiger, R. Overview of Superconductivity and Challenges in Applications. Reviews of Accelerator Science and Technology. 2012, 5, 1-23.
Patel, M.J.; Agrawal, D.H.; Pathan, A.M. Review on Superconductivity: The Phenomenon Occurred at Low Temperature. National Conferences on Recent Trends in Engineering & Technology. 2011.
Sachdev, S. Entangling Superconductivity and Antiferromagnetism. Science. 2012, 336, 1510-1511.
Wilson, N.W. 100 Years of Superconductivity and 50 Years of Superconducting Magnets. IEEE Transactions on Applied Superconductivity. 2012, 22, 3.