Quantum Channel Construction with Circuit Quantum Electrodynamics

Authors: 
Shen, Chao and Noh, Kyungjoo and Albert, Victor V. and Krastanov, Stefan and Devoret, M. H. and Schoelkopf, R. J. and Girvin, S. M. and Jiang, Liang
Name of the Journal: 
Phys. Rev. B
Date of Pub: 
April
Year of Publication: 
2017
Volume: 
95
Issue: 
13
Pages: 
134501
Publisher Name, Address and Year: 
American Physical Society
Abstract: 

Quantum channels can describe all transformations allowed by quantum mechanics. We adapt two existing works [S. Lloyd and L. Viola, Phys. Rev. A 65, 010101 (2001) and E. Andersson and D. K. L. Oi, Phys. Rev. A 77, 052104 (2008)] to superconducting circuits, featuring a single qubit ancilla with quantum nondemolition readout and adaptive control. This construction is efficient in both ancilla dimension and circuit depth. We point out various applications of quantum channel construction, including system stabilization and quantum error correction, Markovian and exotic channel simulation, implementation of generalized quantum measurements, and more general quantum instruments. Efficient construction of arbitrary quantum channels opens up exciting new possibilities for quantum control, quantum sensing, and information processing tasks.