Abstract:

The area of quantum communication complexity searches for communication tasks that can be solved more efficiently using quantum states as carriers of information rather than their classical counterparts. Some of these protocols show an exponential savings in communication resources when operating in the quantum domain. Will it be possible to realize this abstract advantage in practical quantum optical implementations? The long-term goal would be to find protocols that convince a classical optical communication engineer that using the quantum domain is preferable. But there is no bonus point for saying 'quantum' ... we need to measure success in terms of resources as counted by the classical optical communication engineer.

In this talk we will present a specific quantum communication protocol that can be implemented using laser pulses and linear optics and which beats classical communication. The measure is usage of Hilbert space dimensions, which translates to a significant reduction in required optical power levels and leakage of information. While this alone might not convince a classical optical communication engineer (yet?), we will show how our findings change the current view of communication complexity as a purely theoretical field without practical impact.

(PLEASE NOTE NON-STANDARD LOCATION)