### Abstract

Original language | English |
---|---|

Number of pages | 22 |

Journal | New Journal of Physics |

Volume | 9 |

Issue number | Oct |

DOIs | |

Publication status | Published - 29 Oct 2007 |

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### Keywords

- qubit
- subspace
- fourier spectrum
- quantum computation
- subspace leakage

### Cite this

*New Journal of Physics*,

*9*(Oct). https://doi.org/10.1088/1367-2630/9/10/384

}

*New Journal of Physics*, vol. 9, no. Oct. https://doi.org/10.1088/1367-2630/9/10/384

**Subspace confinement : how good is your qubit?** / Devitt, Simon J.; Schirmer, Sonia G.; Oi, Daniel K.L.; Cole, Jared H.; Hollenberg, Lloyd C.L.

Research output: Contribution to journal › Article

TY - JOUR

T1 - Subspace confinement

T2 - how good is your qubit?

AU - Devitt, Simon J.

AU - Schirmer, Sonia G.

AU - Oi, Daniel K.L.

AU - Cole, Jared H.

AU - Hollenberg, Lloyd C.L.

PY - 2007/10/29

Y1 - 2007/10/29

N2 - The basic operating element of standard quantum computation is the qubit, an isolated two-level system that can be accurately controlled, initialized and measured. However, the majority of proposed physical architectures for quantum computation are built from systems that contain much more complicated Hilbert space structures. Hence, defining a qubit requires the identification of an appropriate controllable two-dimensional sub-system. This prompts the obvious question of how well a qubit, thus defined, is confined to this subspace, and whether we can experimentally quantify the potential leakage into states outside the qubit subspace. We demonstrate how subspace leakage can be characterized using minimal theoretical assumptions by examining the Fourier spectrum of the oscillation experiment.

AB - The basic operating element of standard quantum computation is the qubit, an isolated two-level system that can be accurately controlled, initialized and measured. However, the majority of proposed physical architectures for quantum computation are built from systems that contain much more complicated Hilbert space structures. Hence, defining a qubit requires the identification of an appropriate controllable two-dimensional sub-system. This prompts the obvious question of how well a qubit, thus defined, is confined to this subspace, and whether we can experimentally quantify the potential leakage into states outside the qubit subspace. We demonstrate how subspace leakage can be characterized using minimal theoretical assumptions by examining the Fourier spectrum of the oscillation experiment.

KW - qubit

KW - subspace

KW - fourier spectrum

KW - quantum computation

KW - subspace leakage

U2 - 10.1088/1367-2630/9/10/384

DO - 10.1088/1367-2630/9/10/384

M3 - Article

VL - 9

JO - New Journal of Physics

JF - New Journal of Physics

SN - 1367-2630

IS - Oct

ER -