Multiple data access via a common cavity bus in circuit QED. (20th March 2017)

• Record Type: Journal Article
• Authors: Chatterjee, Dibyendu; Roy, Arijit
• Other Names: Civalleri Pier Paolo guestEditor.; Csurgay Árpád I. guestEditor.; Porod Wolfgang guestEditor.
• Is Part Of: International journal of circuit theory and applications. Volume 45:Number 7(2017:Jul.)
• Page Start: 970
• Page End: 988
• Publication Date: 2017-03-20
• Subjects: circuit QED -- multiplexer -- demultiplexer -- transmon -- quprocessor; Electric circuit analysis -- Periodicals; 621.319205
• DOI: 10.1002/cta.2331
• Languages: English
• ISSNs: 0098-9886

Abstract

Summary: Accessing multiple data through a common bus in quantum information processing is challenging. Experimental demonstration of quantum state transfer between a pair of superconducting phase qubit [M. A. Sillanpää et al ., Nature449, 438 (2007)] motivates us to construct a scheme for accessing and transferring multi‐qubit quantum information through a common cavity bus. Here, we have presented an efficient scheme to access multiple data through single channel using superconducting qubit and superconducting cavity resonator. The qubit–cavity photon coupling offers transfer of quantum data in different location of a quantum processing system from multiple users through a common superconducting cavity resonator. Instead of phase qubit, charge qubit is found to be more advantageous in qubit–cavity interaction for quantum data transformation, because charge qubit is immune to flux and external flux is used to select specific qubit from a set of qubits. The scheme is very generic and provides M‐output from N‐number of inputs via a common cavity in circuit quantum electrodynamics. The flexibility of the scheme allows us to implement multiplexer, demultiplexer, and so on for quantum data manipulation in a similar manner as in classical digital electronics. This scheme is useful to reduce the circuit complexity in quantum processor named as 'quprocessor'. Copyright © 2017 John Wiley & Sons, Ltd. Abstract : This paper proposes a new scheme of multiplex–demultiplex system for quantum information with superconducting circuit quantum electrodynamics devices. In this system, many superconducting qubits (flux qubits, transmons) are connected to a single resonator. The resonator is used as a quantum information bus. One can control the effective coupling strength between a qubit and the bus by tuning the qubit parameter (qubit frequency) and a cavity parameter with local magnetic fields. Then, one can exchange quantum information between any two of qubits via the bus using coupling and decoupling. Our scheme is very useful for realization of quantum processor.