Vulnerability of Satellite Quantum Key Distribution to Disruption from Ground-Based Lasers.

Area of Science:

• Quantum communication
• Satellite technology
• Cybersecurity

Background:

• Satellite-mediated quantum key distribution (QKD) is crucial for long-distance quantum-secure communication.
• While inherently resistant to eavesdropping, satellite QKD systems face potential disruption vulnerabilities.

Purpose of the Study:

• To investigate the vulnerability of satellite QKD systems to disruption by ground-based lasers.
• To model and quantify the impact of laser-induced noise on QKD performance.

Main Methods:

• Development of an atmospheric attenuation and satellite optical scattering model.
• Estimation of excess noise photon rates injected into the QKD channel.
• Calculation of the quantum bit error rate (QBER) under laser disruption.

Main Results:

• A 1 kW ground-based laser can significantly disrupt satellite QKD systems.
• Scattered photons from the laser can be detected by the QKD receiver.
• Commercial availability of such lasers poses a practical threat.

Conclusions:

• Satellite QKD systems are vulnerable to disruption by readily available ground-based lasers.
• This disruption method poses a significant threat to the security of high-value satellite communications.
• Countermeasures against laser-based disruption are necessary for future QKD systems.