dorsal/arxiv
View SchemaAn exact effective two-qubit gate in a chain of three spins
| Authors | Man-Hong Yung, Debbie W. Leung, Sougato Bose |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0312105 |
| URL | https://arxiv.org/abs/quant-ph/0312105 |
| Journal | Quantum Information and Computation 4, 174 (2004) |
Abstract
We show that an effective two-qubit gate can be obtained from the free evolution of three spins in a chain with nearest neighbor XY coupling, without local manipulations. This gate acts on the two remote spins and leaves the mediating spin unchanged. It can be used to perfectly transfer an arbitrary quantum state from the first spin to the last spin or to simultaneously communicate one classical bit in each direction. One ebit can be generated in half of the time for state transfer. For longer spin chains, we present methods to create or transfer entanglement between the two end spins in half of the time required for quantum state transfer, given tunable coupling strength and local magnetic field. We also examine imperfect state transfer through a homogeneous XY chain.
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"abstract": "We show that an effective two-qubit gate can be obtained from the free\nevolution of three spins in a chain with nearest neighbor XY coupling, without\nlocal manipulations. This gate acts on the two remote spins and leaves the\nmediating spin unchanged. It can be used to perfectly transfer an arbitrary\nquantum state from the first spin to the last spin or to simultaneously\ncommunicate one classical bit in each direction. One ebit can be generated in\nhalf of the time for state transfer.\n For longer spin chains, we present methods to create or transfer entanglement\nbetween the two end spins in half of the time required for quantum state\ntransfer, given tunable coupling strength and local magnetic field. We also\nexamine imperfect state transfer through a homogeneous XY chain.",
"arxiv_id": "quant-ph/0312105",
"authors": [
"Man-Hong Yung",
"Debbie W. Leung",
"Sougato Bose"
],
"categories": [
"quant-ph"
],
"journal_ref": "Quantum Information and Computation 4, 174 (2004)",
"title": "An exact effective two-qubit gate in a chain of three spins",
"url": "https://arxiv.org/abs/quant-ph/0312105"
},
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