{
  "id": "1302.0882",
  "version": "v1",
  "published": "2013-02-04T21:55:39.000Z",
  "updated": "2013-02-04T21:55:39.000Z",
  "title": "Measurement of a qubit and measurement with a qubit",
  "authors": [
    "Antonio Di Lorenzo"
  ],
  "comment": "18 pages, 1 figure, 1 table. Comments welcome",
  "categories": [
    "quant-ph"
  ],
  "abstract": "Generally, the measurement process consists in coupling a system to a detector that can give a continuous output. However, it may be interesting to use as a detector a system with a discrete spectrum, especially in view of applications to quantum information. Here, we study 1) a two-level system measuring another two-level system (qubit); 2) a generic system measuring a qubit; 3) a qubit measuring a generic system. The results include the case when a postselection on the measured system is made. We provide the exact solution, and also a controlled expansion in the coupling parameter, giving formulas valid in the weak measurement regime for arbitrary preparation and postselection. The concept of generalized Wigner functions is introduced.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2013-02-04T21:55:39.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "two-level system",
      "generic system",
      "measurement process consists",
      "weak measurement regime",
      "postselection"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 18,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "adsabs": "2013arXiv1302.0882D"
    }
  }
}