Optimized Protocols for Duplex Quantum Transduction

Area of Science:

• Quantum Information Science
• Quantum Communication Networks
• Quantum Transduction

Background:

• Quantum transducers are crucial for quantum networks, interfacing different physical platforms.
• Unidirectional quantum transduction performance is assessed using quantum channel capacity.
• Characterizing duplex (bidirectional) quantum transducer performance is an open challenge.

Purpose of the Study:

• To develop a framework for characterizing duplex quantum transducer performance.
• To compare simultaneous duplex transduction with time-shared unidirectional transduction.
• To extend the characterization to transducers with finite bandwidth.

Main Methods:

• Proposal of 'rate regions' as a tool to quantify duplex quantum transduction performance.
• Analysis of simultaneous duplex transduction strategies.
• Integration over the frequency domain to account for finite bandwidth.

Main Results:

• Rate regions provide a method to characterize duplex quantum transduction.
• Simultaneous duplex transduction can achieve higher performance than time-shared protocols.
• The rate region framework successfully characterizes transducers with finite bandwidth.

Conclusions:

• Rate regions offer a novel approach to evaluate duplex quantum transducers.
• Optimized simultaneous operation is a promising strategy for quantum network development.
• The developed framework is applicable to practical quantum transducer characterization.