dorsal/arxiv
View SchemaA measurement-based measure of the size of macroscopic quantum superpositions
| Authors | Jan Ivar Korsbakken, K. Birgitta Whaley, Jonathan DuBois, J. Ignacio Cirac |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0611121 |
| URL | https://arxiv.org/abs/quant-ph/0611121 |
| DOI | 10.1103/PhysRevA.75.042106 |
| Journal | Phys. Rev. A 75, 042106 (2007) |
Abstract
Recent experiments claiming formation of quantum superposition states in near macroscopic sys- tems raise the question of how the sizes of general quantum superposition states in an interacting system are to be quantified. We propose here a measure of size for such superposition states that is based on what measurements can be performed to probe and distinguish the different branches of the state. The measure allows comparison of the effective size for superposition states in very different physical systems. It can be applied to a very general class of superposition states and reproduces known results for near-ideal cases. Comparison with a prior measure based on analy- sis of coherence between branches indicates that significantly smaller effective superposition sizes result from our measurement-based measure. Application to a system of interacting bosons in a double-well trapping potential shows that the effective superposition size is strongly dependent on the relative magnitude of the barrier height and interparticle interaction.
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"abstract": "Recent experiments claiming formation of quantum superposition states in near\nmacroscopic sys- tems raise the question of how the sizes of general quantum\nsuperposition states in an interacting system are to be quantified. We propose\nhere a measure of size for such superposition states that is based on what\nmeasurements can be performed to probe and distinguish the different branches\nof the state. The measure allows comparison of the effective size for\nsuperposition states in very different physical systems. It can be applied to a\nvery general class of superposition states and reproduces known results for\nnear-ideal cases. Comparison with a prior measure based on analy- sis of\ncoherence between branches indicates that significantly smaller effective\nsuperposition sizes result from our measurement-based measure. Application to a\nsystem of interacting bosons in a double-well trapping potential shows that the\neffective superposition size is strongly dependent on the relative magnitude of\nthe barrier height and interparticle interaction.",
"arxiv_id": "quant-ph/0611121",
"authors": [
"Jan Ivar Korsbakken",
"K. Birgitta Whaley",
"Jonathan DuBois",
"J. Ignacio Cirac"
],
"categories": [
"quant-ph"
],
"doi": "10.1103/PhysRevA.75.042106",
"journal_ref": "Phys. Rev. A 75, 042106 (2007)",
"title": "A measurement-based measure of the size of macroscopic quantum superpositions",
"url": "https://arxiv.org/abs/quant-ph/0611121"
},
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