Implementing quantum gates through scattering between a static and a flying qubit
- Departamento de Fisica Aplicada, Cinvestav-Merida A.P. 73, Merida, Yucatan 97310 (Mexico)
- CNISM and Dipartimento di Fisica e Tecnologie Relative, Universita degli Studi di Palermo, Viale delle Scienze, Edificio 18, I-90128 Palermo (Italy)
- CEMAPRE, ISEG, Universidade Tecnica de Lisboa, P-1200-781, and SQIG, Instituto de Telecomunicacoes, P-1049-001 Lisbon (Portugal)
- Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)
We investigate whether a two-qubit quantum gate can be implemented in a scattering process involving a flying and a static qubit. To this end, we focus on a paradigmatic setup made out of a mobile particle and a quantum impurity, whose respective spin degrees of freedom couple to each other during a one-dimensional scattering process. Once a condition for the occurrence of quantum gates is derived in terms of spin-dependent transmission coefficients, we show that this can be actually fulfilled through the insertion of an additional narrow potential barrier. An interesting observation is that under resonance conditions this procedure enables a gate only for isotropic Heisenberg (exchange) interactions and fails for an XY interaction. We show the existence of parameter regimes for which gates able to establish a maximum amount of entanglement can be implemented. The gates are found to be robust to variations of the optimal parameters.
- OSTI ID:
- 21528592
- Journal Information:
- Physical Review. A, Vol. 82, Issue 5; Other Information: DOI: 10.1103/PhysRevA.82.052313; (c) 2010 The American Physical Society; ISSN 1050-2947
- Country of Publication:
- United States
- Language:
- English
Similar Records
Controlled-not gate with weakly coupled qubits: Dependence of fidelity on the form of interaction
A controlled-NOT gate for frequency-bin qubits
Related Subjects
GENERAL PHYSICS
97 MATHEMATICAL METHODS AND COMPUTING
DEGREES OF FREEDOM
EXCHANGE INTERACTIONS
ONE-DIMENSIONAL CALCULATIONS
QUANTUM ENTANGLEMENT
QUBITS
RESONANCE
SCATTERING
SPIN
TRANSMISSION
ANGULAR MOMENTUM
INFORMATION
INTERACTIONS
PARTICLE PROPERTIES
QUANTUM INFORMATION