From UPSC perspective, the following things are important :
Prelims level: Superconductivity
Mains level: Not Much
Central Idea
- Recently, two South Korean researchers sparked excitement in the physics community by claiming to have achieved Superconductivity at room temperature.
- They claim to have developed a lead-based compound exhibiting superconducting properties at normal room temperature and pressure (NTP) conditions.
NTP (Normal Temperature and Pressure):Normal Temperature: Defined as 20 degrees Celsius (20°C) or 293.15 Kelvin (K). Normal Pressure: Defined as 1 atmosphere (atm) or 101.325 kilopascals (kPa), which is the same pressure as STP. NTP is another standard set of conditions used for specific applications, but it is less commonly used than STP. STP (Standard Temperature and Pressure):Standard Temperature: Defined as 0 degrees Celsius (0°C) or 273.15 Kelvin (K). At this temperature, the average kinetic energy of gas molecules is minimal. Standard Pressure: Defined as 1 atmosphere (atm) or 101.325 kilopascals (kPa). This is the average atmospheric pressure at sea level. STP is often used to express gas properties and perform calculations under uniform conditions to allow for meaningful comparisons between different gases or processes. |
What is Superconductivity?
- Zero Resistance: Superconductivity occurs when a material offers almost zero resistance to the flow of electric current, enabling energy-efficient electrical appliances and lossless power transmission.
- Magnetic Behavior: Superconductors also display fascinating behavior under magnetic fields, enabling technologies like MRI machines and superfast Maglev trains.
Exploring the Material LK-99
- Apatite Structure: The Korean group utilized copper-substituted lead apatite, a phosphate mineral with unique tetrahedral motifs, to create LK-99.
- Superconducting Behavior: LK-99 displayed essential superconducting properties, with almost zero resistance to current flow and sudden emergence of resistance above a critical current threshold.
- Magnetic Resilience: LK-99 retained superconductivity even under the presence of a magnetic field until reaching a critical threshold.
Current Superconductors and Their Limitations
- Earlier Discoveries: In the 1980s, scientists found copper oxide materials exhibiting superconductivity above -240°C. Subsequent research yielded limited success in achieving higher temperatures.
- Extreme Conditions: Existing superconductors operate at extremely low temperatures, often below -250°C, close to absolute zero (-273°C).
- Critical Temperatures: Materials like Mercury, Lead, and Aluminum, Tin, and Niobium exhibit superconductivity at critical temperatures just above absolute zero.
- High-Temperature Superconductors: Some materials, labelled ‘high-temperature’ superconductors, display superconducting properties below -150°C.
Scientific Community’s Response
- Cautious Optimism: The scientific community responded cautiously to the claims of LK-99’s room-temperature superconductivity, given previous controversies and unverified claims.
- Technical Errors: Some data in the research papers raised questions and were deemed “sloppy” or “fishy” by independent scientists.
- Replication Efforts: Numerous research groups worldwide are attempting to reproduce the results to validate the claim.
- Mixed Perspectives: The authors’ unwavering confidence in their work contrasts with certain aspects of the research that appear hurried or contentious.
Conclusion
- The search for room-temperature superconductors represents a holy grail in science, promising immense rewards and recognition.
- Although the recent claim by South Korean researchers has captured attention, it awaits rigorous validation.
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024
