Advanced Development for Defense Science and Technology: Measurement Tools for Quantum Information Processing

Quantitative and visually intuitive information is critical to understanding, designing, and verifying the operation of any system. For instance, a vector signal analyzer allows a designer to gain an immediate understanding of a radio communications link by visualizing the transmission signal constellation. Additional analysis such as a calculation of the error vector magnitude can be performed in real time. Such tools are now an indispensable part of modern engineering methods. Quantum state tomography is a measurement tool which allows for complete characterization of quantum states. Truly quantum systems like networks of entangled states will need measurement tools that measure quantum signals (states) just as classical systems need measurement tools to measure classical signals. Although great progress has been made in tomography techniques, no commercial equipment currently exists. Advances in the field of quantum information are severely hampered because every development group must build their own tools including even basic measurement devices. It is the goal of this Phase-I SBIR to develop the component and systems technology to design a practical polarization-mode quantum state tomography system. We will pursue methods of making the signal acquisition and analysis as fast as possible to give the user a real-time feel. A prototype system will be built and characterized in Phase-II.