Proposed Research D01：

Realization of quantum cybernetics using photonic quantum circuits

We will build a combined quantum-control test bed based on the concept of quantum cybernetics and realize optimal quantum information control, particularly decoherence control. For this purpose, we will make use of the characteristics of photons such as their good controllability and ease of interface with atoms and molecules as well as artificial atoms, and the presence of the largest quantum circuits combining linear optical devices and projection measurement.

Quantum cybernetics is an essential research area for realizing and scaling up of quantum information processing. In this field, coherent quantum information control is performed by integrating a quantum system consisting of information-carrying units, the input and output of the system, and a set of macroscopic devices to control the input and output operations, into an inseparable system with causal relationships among them. Research using a test bed of an appropriate size is important to understand such systems. In this respect, the photon has advantages such as good controllability and ease of interface with atoms and molecules as well as artificial atoms.

Our group has succeeded in developing a two-photon quantum filter, one of the most advanced linear optical quantum circuits ever developed, in which four quantum gates and a complex pass interference are integrated. Making use of our accumulated knowledge, we will build a combined quantum-control test bed based on the concept of quantum cybernetics and realize optimal quantum information control, particularly decoherence control. More specifically, we will also conduct research aiming to control of a quantum state between dissimilar quanta using a photon quantum bit as a medium. We will also try to develop optical devices with built-in quantum control using nanophotonics technology.

Details : 「Publications」