NPL reveals Quantum Local Area Network (QLAN) advances

2 minute read

Quantum networks are expected to form the backbone of future quantum technologies, enabling applications such as secure communications, distributed quantum computing and enhanced quantum sensing. While many quantum networking demonstrations have been achieved in controlled laboratory environments, deploying these systems in realistic operating conditions presents significant technical challenges. 

One key challenge is the precise synchronisation of remote detection systems. To identify entangled or correlated photons exchanged between distant network nodes, timing synchronisation must be maintained at the picosecond level despite environmental fluctuations and delays introduced by optical fibre links. 

Recently, NPL researchers successfully demonstrated two important capabilities on the NPL Quantum Local Area Network (QLAN), a three-user quantum network connecting measurement systems located in different laboratories via deployed optical fibres. First, the team confirmed the distribution of energy-time entanglement between remote user nodes. Secondly, they achieved picosecond-level time synchronisation across the network. 

The work represents an important step towards deploying robust quantum networking technologies outside the laboratory and demonstrates NPL's capability to combine quantum and timing expertise to address real-world challenges in future quantum infrastructure.