Why in news: related to the functioning of GPS- to keep accurate timing across different time zones. (Hindu-06/12/2023)

1.Principle of Atomic Clocks: Atomic clocks use the resonance frequencies of atoms as their basis for timekeeping, relying on the consistent electronic transitions within specific elements like cesium, hydrogen, or rubidium.

2.Evolution of Atomic Clocks: In 1945, Isidor Rabi’s atomic beam magnetic resonance concept laid the groundwork. By 1949, the National Bureau of Standards created the first atomic clock using ammonia molecules, followed by the introduction of the cesium-based NBS-1 in 1952.

3.Types of Atomic Clocks:

   –Cesium Atomic Clocks: Employ a magnetic field to separate cesium atoms of different energy levels.

   –Hydrogen Atomic Clocks: Maintain hydrogen atoms at a consistent energy level within specialized containers.

   –Rubidium Atomic Clocks: Utilize rubidium gas in a glass cell, altering light absorption at the rubidium frequency.

4.Precision and Accuracy: Atomic clocks boast incredible accuracy, with an error rate as low as 1 second in up to 100 million years, making them among the most precise timekeeping devices.

5.Global Contribution: About 400 atomic clocks globally contribute to International Atomic Time (TAI), a foundational standard for determining Coordinated Universal Time (UTC) and local times worldwide.

6.Utility in Navigation Systems: Satellite navigation systems such as GPS, GLONASS, and Galileo heavily rely on atomic clocks for precise time measurements, ensuring accurate positioning calculations.