Deterministic amplification of Schrödinger cat states in circuit quantum electrodynamics

Jaewoo Joo*, Matthew Elliott, Daniel K.L. Oi, Eran Ginossar, Timothy P. Spiller

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

23 Downloads (Pure)


Perfect deterministic amplification of arbitrary quantum states is prohibited by quantum mechanics, but determinism can be achieved by compromising between fidelity and amplification power. We propose a dynamical scheme for deterministically amplifying photonic Schrödinger cat states, which show great promise as a tool for quantum information processing. Our protocol is designed for strongly coupled circuit quantum electrodynamics and utilizes artificial atomic states and external microwave controls to engineer a set of optimal state transfers and achieve high fidelity amplification. We compare analytical results with full simulations of the open, driven Jaynes-Cummings model, using realistic device parameters for state of the art superconducting circuits. Amplification with a fidelity of 0.9 can be achieved for sizable cat states in the presence of cavity and atomic-level decoherence. This tool could be applied to practical continuous-variable information processing for the purification and stabilization of cat states in the presence of photon losses.

Original languageEnglish
Article number023028
Number of pages10
JournalNew Journal of Physics
Issue number2
Publication statusPublished - 5 Feb 2016


  • amplification of quantum states
  • cat states
  • circuit quantum electrodynamics
  • quantum optics
  • superconducting circuits
  • RCUK
  • EP/L026082/1
  • EP/M013472/1


Dive into the research topics of 'Deterministic amplification of Schrödinger cat states in circuit quantum electrodynamics'. Together they form a unique fingerprint.

Cite this