### Abstract

Recently, it has been suggested that it may be possible to use combinations of coupled quantum wire waveguides to form quantum computational qubits [1],[2]. However, there are several related problems intrinsic to this approach. First, in order to completely switch the electron probability wave from one waveguide to another, the length of the region in which the two waveguides are coupled must be tuned quite precisely. In addition, even with a well-tuned coupling length, it appears that complete transmission of the probability wave cannot be achieved [2]. Both of these problems may be mitigated by the addition of a bias along the length of the quantum wires - this would effectively alter the coupling length and may also increase the transmission gain. We show that adding this bias does not provide gain to overcome the lack of 100% coupling, between the two guides, but can be used to compensate for imprecision in the length of the device's coupling region.

Original language | English (US) |
---|---|

Title of host publication | 2002 International Conference on Computational Nanoscience and Nanotechnology - ICCN 2002 |

Editors | M. Laudon, B. Romanowicz |

Pages | 231-234 |

Number of pages | 4 |

State | Published - 2002 |

Event | 2002 International Conference on Computational Nanoscience and Nanotechnology - ICCN 2002 - San Juan, Puerto Rico Duration: Apr 21 2002 → Apr 25 2002 |

### Other

Other | 2002 International Conference on Computational Nanoscience and Nanotechnology - ICCN 2002 |
---|---|

Country | Puerto Rico |

City | San Juan |

Period | 4/21/02 → 4/25/02 |

### Fingerprint

### Keywords

- Coupled quantum wires
- Mode-matching
- Quantum waveguide
- Qubit

### ASJC Scopus subject areas

- Engineering(all)

### Cite this

*2002 International Conference on Computational Nanoscience and Nanotechnology - ICCN 2002*(pp. 231-234)

**Gain in a semiconductor waveguide qubit.** / Harris, J.; Ferry, D. K.; Akis, R.

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution

*2002 International Conference on Computational Nanoscience and Nanotechnology - ICCN 2002.*pp. 231-234, 2002 International Conference on Computational Nanoscience and Nanotechnology - ICCN 2002, San Juan, Puerto Rico, 4/21/02.

}

TY - GEN

T1 - Gain in a semiconductor waveguide qubit

AU - Harris, J.

AU - Ferry, D. K.

AU - Akis, R.

PY - 2002

Y1 - 2002

N2 - Recently, it has been suggested that it may be possible to use combinations of coupled quantum wire waveguides to form quantum computational qubits [1],[2]. However, there are several related problems intrinsic to this approach. First, in order to completely switch the electron probability wave from one waveguide to another, the length of the region in which the two waveguides are coupled must be tuned quite precisely. In addition, even with a well-tuned coupling length, it appears that complete transmission of the probability wave cannot be achieved [2]. Both of these problems may be mitigated by the addition of a bias along the length of the quantum wires - this would effectively alter the coupling length and may also increase the transmission gain. We show that adding this bias does not provide gain to overcome the lack of 100% coupling, between the two guides, but can be used to compensate for imprecision in the length of the device's coupling region.

AB - Recently, it has been suggested that it may be possible to use combinations of coupled quantum wire waveguides to form quantum computational qubits [1],[2]. However, there are several related problems intrinsic to this approach. First, in order to completely switch the electron probability wave from one waveguide to another, the length of the region in which the two waveguides are coupled must be tuned quite precisely. In addition, even with a well-tuned coupling length, it appears that complete transmission of the probability wave cannot be achieved [2]. Both of these problems may be mitigated by the addition of a bias along the length of the quantum wires - this would effectively alter the coupling length and may also increase the transmission gain. We show that adding this bias does not provide gain to overcome the lack of 100% coupling, between the two guides, but can be used to compensate for imprecision in the length of the device's coupling region.

KW - Coupled quantum wires

KW - Mode-matching

KW - Quantum waveguide

KW - Qubit

UR - http://www.scopus.com/inward/record.url?scp=6344221925&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=6344221925&partnerID=8YFLogxK

M3 - Conference contribution

AN - SCOPUS:6344221925

SN - 0970827563

SN - 9780970827562

SP - 231

EP - 234

BT - 2002 International Conference on Computational Nanoscience and Nanotechnology - ICCN 2002

A2 - Laudon, M.

A2 - Romanowicz, B.

ER -