Group Members: Erick Iciarte Kelly Mann Daniel Willis Miguel Lastres

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Ralph George
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1 Group Members: Erick Iciarte Kelly Mann Daniel Willis Miguel Lastres

2 How it works A superconductor is a material that exhibits zero resistance when exposed to very cold temperatures. Temperatures required for super conductance range from -234 C or -398 F and beyond. They will no longer poses their low resistive states when placed in the presence of too large a magnetic field.

3 Super conductance only occurs when the material cools below it s critical temperature. Like a critical temperature, there is also a critical magnetic field. Superconductors will cease to super conduct when an external magnetic field is applied that exceeds the critical magnetic field.

Electric currents are set up near the surface.

4 Meissner Effect The Meissner Effect refers to the complete expulsion of magnetic fields from the interior of a superconductor. The magnetic field intensity is zero within the superconductor. Electric currents are set up near the surface. Their resulting magnetic fields cancel the internally applied magnetic field. These current are know as persistent currents. Persistent currents are the reason there are Superconductors.

5 Types of Superconductors There are type 1 and type 2 superconductors. Type 1 superconductors were discovered first and require the coldest temperatures to exhibit super conductance. Type 1 superconductors have perfect diamagnetism. Type 1 superconductors only have 1 critical magnetic field and as a result, are not versatile.

Type 2 Superconductor Main difference is that type 2 superconductors have 2 critical magnetic fields. Used in MRI machines. Below the lower critical field, the material will super conduct.

6 Type 2 Superconductor Main difference is that type 2 superconductors have 2 critical magnetic fields. Used in MRI machines. Below the lower critical field, the material will super conduct. Above the upper critical field, the material will cease to super conduct. In-between the two levels is a mixed state in which some parts of the metal super conduct as opposed to other parts of the material the conduct electricity normally. The closer the magnetic field is to the upper critical field, the less superconductive it becomes. As a result, type 2 semiconductors can exhibit their superconductivity in the presence of greater magnetic fields.

7 Quantum Levitation Done by a quantum effect called quantum locking also called flux pinning. Only type-ii superconductors can be penetrated by magnetic fields. Flux pinning is closely related to the Meissnet Effect but with the difference that it allows the magnetic flux to enter in quantized packets which form the flux tubes.

8 1 µm thick superconducting disk super cooled with liquid nitrogen. Super cooling provides less energy to knock electrons from there initial path. Flux Tubes

9 Hula hoop Ring MagSurf

10 SQUID Superconducting Quantum Interference Device

11 What is a SQUID??? A superconducting quantum interference device (SQUID) Josephson Junction SQUID Design

12 SQUID Uses One of the device's most promising uses is in magnetoencephalography (MEG). Physical processes. DC SQUIDs Atomic Magnetometer Example SQUID Helmet

13 Heike Kamerlingh Onnes discovered superconductivity on April 8, 1911 At 4.2 K the resistance in a solid mercury wire immersed in liquid helium suddenly vanished Nobel prize in 1913 Many have continued the research he started many decades ago

function in the medical field - - more precise than MRI

14 Uses of Superconductors Transport vehicles, such as trains MLX01 test vehicle attained a speed of 361 mph Performs a life-saving function in the medical field - - more precise than MRI Transmission of commercial power to cities not practical over long distances

15 The Research Continues UTK is collaborating with ORNL to probe enzyme function by using a superconducting magnet and supercomputing Tennessee Tech has been awarded a project by the DOE that features a feasibility study of superconducting cables

16 China s Tsinghua University and U.S. DOE s Berkley Lab are working on high-temperature superconductivity

17 Last, but not least, we can t forget our favorite teacher!

18 Citation

What s so super about superconductivity?

What s so super about superconductivity? Mark Rzchowski Physics Department Electrons can flow through the wire when pushed by a battery. Electrical resistance But remember that the wire is made of atoms.