dorsal/arxiv
View SchemaOn the effective size of certain "Schr\"{o}dinger cat'' like states
| Authors | Wolfgang Dür, Christoph Simon, J. Ignacio Cirac |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0205099 |
| URL | https://arxiv.org/abs/quant-ph/0205099 |
| DOI | 10.1103/PhysRevLett.89.210402 |
| Journal | Phys. Rev. Lett. 89, 210402 (2002) |
Abstract
Several experiments and experimental proposals for the production of macroscopic superpositions naturally lead to states of the general form $|\phi_1>^{\otimes N}+|\phi_2>^{\otimes N}$, where the number of subsystems $N$ is very large, but the states of the individual subsystems have large overlap, $|{\l}\phi_1|\phi_2 \r|^2=1-\epsilon^2$. We propose two different methods for assigning an effective particle number to such states, using ideal Greenberger--Horne--Zeilinger (GHZ)-- states of the form $|0\r^{\otimes n}+|1\r^{\otimes n}$ as a standard of comparison. The two methods are based on decoherence and on a distillation protocol respectively. Both lead to an effective size $n$ of the order of $N \epsilon^2$.
{
"annotation_id": "66541f0a-737d-473f-9b72-62e54a181f36",
"date_created": "2026-03-02T18:01:52.883000Z",
"date_modified": "2026-03-02T18:01:52.883000Z",
"file_hash": "b2651acc0bf707b6cc4ded932653865076e71e939e555567b33265850310c6c9",
"private": false,
"record": {
"abstract": "Several experiments and experimental proposals for the production of\nmacroscopic superpositions naturally lead to states of the general form\n$|\\phi_1\u003e^{\\otimes N}+|\\phi_2\u003e^{\\otimes N}$, where the number of subsystems $N$\nis very large, but the states of the individual subsystems have large overlap,\n$|{\\l}\\phi_1|\\phi_2 \\r|^2=1-\\epsilon^2$. We propose two different methods for\nassigning an effective particle number to such states, using ideal\nGreenberger--Horne--Zeilinger (GHZ)-- states of the form $|0\\r^{\\otimes\nn}+|1\\r^{\\otimes n}$ as a standard of comparison. The two methods are based on\ndecoherence and on a distillation protocol respectively. Both lead to an\neffective size $n$ of the order of $N \\epsilon^2$.",
"arxiv_id": "quant-ph/0205099",
"authors": [
"Wolfgang D\u00fcr",
"Christoph Simon",
"J. Ignacio Cirac"
],
"categories": [
"quant-ph"
],
"doi": "10.1103/PhysRevLett.89.210402",
"journal_ref": "Phys. Rev. Lett. 89, 210402 (2002)",
"title": "On the effective size of certain \"Schr\\\"{o}dinger cat\u0027\u0027 like states",
"url": "https://arxiv.org/abs/quant-ph/0205099"
},
"schema_id": "dorsal/arxiv",
"source": {
"execution_id": "589353da-09f2-4ae4-8c71-17ad3c75d3a9",
"id": "arXiv Dataset IDs",
"type": "Model",
"variant": "snapshot-2026-03-01",
"version": "0.1.0"
},
"user_id": 1000002
}