dorsal/arxiv
View SchemaMeasuring the size of a Schroedinger cat state
| Authors | Florian Marquardt, Benjamin Abel, Jan von Delft |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0609007 |
| URL | https://arxiv.org/abs/quant-ph/0609007 |
| DOI | 10.1103/PhysRevA.78.012109 |
| Journal | Phys. Rev. A 78, 012109 (2008). |
Abstract
We propose a measure for the "size" of a Schroedinger cat state, i.e. a quantum superposition of two many-body states with (supposedly) macroscopically distinct properties, by counting how many single-particle operations are needed to map one state onto the other. This definition gives sensible results for simple, analytically tractable cases and is consistent with a previous definition restricted to Greenberger-Horne-Zeilinger-like states. We apply our measure to the experimentally relevant, nontrivial example of a superconducting three-junction flux qubit put into a superposition of left- and right-circulating supercurrent states and find this Schroedinger cat to be surprisingly small.
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"abstract": "We propose a measure for the \"size\" of a Schroedinger cat state, i.e. a\nquantum superposition of two many-body states with (supposedly) macroscopically\ndistinct properties, by counting how many single-particle operations are needed\nto map one state onto the other. This definition gives sensible results for\nsimple, analytically tractable cases and is consistent with a previous\ndefinition restricted to Greenberger-Horne-Zeilinger-like states. We apply our\nmeasure to the experimentally relevant, nontrivial example of a superconducting\nthree-junction flux qubit put into a superposition of left- and\nright-circulating supercurrent states and find this Schroedinger cat to be\nsurprisingly small.",
"arxiv_id": "quant-ph/0609007",
"authors": [
"Florian Marquardt",
"Benjamin Abel",
"Jan von Delft"
],
"categories": [
"quant-ph"
],
"doi": "10.1103/PhysRevA.78.012109",
"journal_ref": "Phys. Rev. A 78, 012109 (2008).",
"title": "Measuring the size of a Schroedinger cat state",
"url": "https://arxiv.org/abs/quant-ph/0609007"
},
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