Dilution Refrigerators

About Dilution Refrigerator

• Dilution refrigerators are specialised cryogenic systems.
• It capable of achieving extremely low temperatures in the millikelvin range, from just above absolute zero up to 1 kelvin(K)
• Working Mechanism:
  • Helium mixture: The refrigerator uses a mixture of helium-3 (³He) and helium-4 (⁴He) to achieve extremely low temperatures.
  • Phase separation: Below 0.87 K, a mixture of helium-3 (³He) and helium-4 (⁴He) separates into a concentrated phase and a dilute phase.
  • Helium-3 movement: When helium-3 moves from the concentrated phase into the dilute phase, more helium-3 moves across to replace it.
  • Cooling: This movement of helium-3 removes heat from the system, producing the extremely low temperatures required by the refrigerator.
• Applications:
  • Quantum applications: It supports the operation and testing of quantum computing platforms and associated quantum technologies.
  • Cryogenic Infrastructureand: Indigenous development can help reduce dependence on imported cryogenic infrastructure and strengthen the domestic quantum technology ecosystem.

DRDO–Zero mK India Project

• DRDO has signed an agreement with Zero mK India Private Ltd., Alwar, Rajasthan.
• 20 mK capability: The proposed refrigerator is designed to achieve 20 mK.
• TDF support: It is the first high-value agreement under the ₹500 crore corpus approved for deep-tech and cutting-edge projects under the Technology Development Fund (TDF) scheme.
• Strategic objective: The project aligns with the National Quantum Mission and strengthens India’s capabilities in quantum technology, advanced cryogenics and strategic technologies.