Quantum Satellite | 24 Dec 2024

Source: TH 

Why in News?

India’s National Quantum Mission (NQM) aims to launch a quantum satellite in 2-3 years, advancing secure communications through quantum physics. This initiative positions India at the forefront of next-gen technology. 

What is a Quantum Satellite? 

• About: A quantum satellite is a communications satellite that employs quantum physics to secure its signals, making it highly resistant to interception. 
  • It utilizes quantum cryptography (a method that uses quantum mechanics to encrypt and transmit data), particularly Quantum Key Distribution (QKD), to protect data by detecting eavesdropping during transmission. 
• Quantum Cryptography: 
  • Encryption Basics: Classical encryption methods, like the Caesar cipher, messages are encoded in a secret code. Without the key, it is not possible for eavesdroppers to decipher the message. 
    • However, these methods are vulnerable to quantum computers, which could crack the code much faster than traditional supercomputers. 
  • Quantum Encryption: It uses quantum key distribution (QKD), to secure messages.  
    • In Quantum Measurement, when a quantum system, such as a photon (a tiny particle of light), is measured, its state changes.  
      • If an eavesdropper attempts to measure the photons carrying a key, this interference alters the state of the photons. As a result, the legitimate parties communicating will immediately detect that the key has been compromised.  
    • Additionally, quantum entanglement ensures that any change to one photon instantly affects the other, making it impossible for an eavesdropper to alter the information without detection. 
    • This makes QKD offer "unconditional security" by detecting any interception, ensuring secure communication. 
• Global Developments in QKD: China currently operates the world’s largest QKD network, which includes three quantum satellites and four ground stations.  
  • India is advancing its quantum communications experiments, with plans for a satellite-based QKD network. Studies by the Raman Research Institute, Bengaluru, suggest that the Indian Astronomical Observatory in Hanle, Ladakh, offers ideal conditions for such a system. 
    • Indian Space Research Organisation (ISRO) has successfully demonstrated free-space Quantum Communication over a distance of 300 m. 
  • The United Nations (UN) has designated the year 2025 as the ‘International Year of Quantum Science and Technology’ to increase public awareness of the importance of quantum science and its applications. 

What are the Limitations of Quantum Key Distribution? 

• Technological Maturity: The technology is still in the experimental phase in India, and commercial implementation of large-scale QKD networks is not yet feasible. 
• Infrastructure Costs: Implementing QKD requires specialized hardware and infrastructure, which increases costs compared to traditional cryptography methods. 
• Integration: Integrating QKD with existing communication networks and ensuring compatibility with classical encryption systems presents a significant technical challenge. 
• Lack of Authentication: QKD doesn’t provide a reliable means to authenticate the source of the transmission, making it vulnerable to potential attacks where an adversary could impersonate a legitimate party. 

What is the National Quantum Mission (NQM)? 

• About: The NQM, launched in 2023 with a Rs. 60,000 crore investment from 2023-24 to 2030-31, aims to advance Quantum Technologies in India and position India as a global leader in Quantum Technologies and Applications (QTA). 
• Objective: The NQM aims to develop quantum computers (build intermediate-scale quantum computers with 50-1000 physical qubits (quantum bits) over 8 years), utilizing superconducting and photonic platforms. 
  • It will establish satellite-based secure quantum communications within 2000 km in India and internationally.  
  • The NQM will support inter-city quantum key distribution over 2000 km and develop multi-node quantum networks. It also focuses on creating atomic clocks for precision applications. 
• Significance: NQM aims to make India a global leader in quantum technologies, surpassing classical physics limits with advanced capabilities beyond current systems. 
• National Priorities: The NQM aligns with and supports national priorities like Digital India, Make in India, Skill India, Start-up India, and Self-reliant India. 
• Implementation: The Mission will establish four Thematic Hubs in collaboration with top academic and National R&D institutes. These hubs will focus on Quantum Computing, Quantum Communication, Quantum Sensing & Metrology, and Quantum Materials & Devices. 
  • These hubs will drive new knowledge and research, advancing quantum technology. 
• Sectoral Impact: The Mission will greatly benefit sectors such as communication, health, financial services, energy, and more. Specific applications include Drug design, Space exploration, and Banking and security. 

Way Forward

• Post-Quantum Cryptography: Due to limitations of QKD, some experts recommend using post-quantum cryptography, which combines quantum-resistant algorithms with classical encryption techniques, offering an alternative to the hardware limitations of QKD. 
• Quantum Authentication: Creation of quantum authentication protocols that ensure both encryption and identity verification will be key. This will close the gap in the security chain and make the system resistant to impersonation and data breaches. 
• Miniaturisation and Robustness: Developing smaller, energy-efficient, and cost-effective quantum devices for scalable deployments will make the technology accessible across industries like defense and healthcare. 
• International Collaboration: Global cooperation is crucial for a standardised and interoperable quantum communication network. India should influence international standards and, through platforms like the  International Telecommunication Union (ITU), ensure its quantum systems are interoperable and meet global security requirements.