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Superconductors

Context
New Material: LK-99
  • Researchers: South Korea
  • Properties: Superconducts at room temperatures.
  • Synthesis: Baking process combining lanarkite and copper phosphide.
  • Characteristics: Exhibits superconductivity at normal air pressure & temperatures up to 127°C.
Definition
Superconductor:
Offers near-zero resistance to electric current
Allows electric current to flow without any loss due to resistance
First Superconductor
Mercury: Exhibits superconductivity at approximately -270°C
Key Concepts
  1. Diamagnetism
    1. Diamagnetism is a fundamental property of all materials, and it refers to the ability of a material to oppose an applied magnetic field
  1. Barden Cooper Schrieffer Pair
    1. Explains that superconductors are diamagnetic, meaning they exhibit a strong repulsion of magnetic fields from their interior
  1. Meissner Effect
    1. Related to the expulsion of a magnetic field from the interior of a superconductor during the transition into the superconducting stage
      Results in trapping a magnetic field within its interior and prevents external fields from penetrating the material
Critical Temperature
  1. The temperature at which materials exhibit superconducting behavior
  1. Above this temperature, materials return to their normal state
  1. Tc varies from Material to Material. Example Tc of LK 99 was 127 Degree Celsius
Applications
  1. MRI
    1. Utilizes superconductors to create strong magnetic fields to align hydrogen atoms
      Often involves the use of cooled helium. Polarises protons in water molecules
  1. Tokamak Reactors
    1. Employs superconductors to control plasma (controlling the confinement and shape of the plasma using magnetic fields) in fusion reactors
  1. Particle Accelerators
    1. Applies superconductors to provide acceleration and control the direction of particle beams
  1. Maglev Trains
    1. Leverages superconductors for magnetic levitation and propulsion of trains
Importance
Current Limitation: No superconductors operate at room temperature and ambient pressure (LK-99 is a notable exception if validated)
Potential Impact: Breakthroughs in superconductor technology have broad applications in medical, energy, and transportation sectors due to efficient energy transfer capabilities.