Abstract
A backaction evading (BAE) measurement apparatus based on simple optics and a parametric downconversion amplifier was previously demonstrated. An important property predicted for the BAE apparatus is that if the input state is the eigenstate of the measured quantity, the output will be in the same state as the input state. This has not been verified in any of the BAE experiments performed to date. An experiment is in progress using two BAE measurements in series. The first BAE measurement of a quadrature component of the input signal yields a readout A. As a direct result of this measurement, the transmitted signal is projected into a near eigenstate with an eigenvalue given by readout A. The larger the gain of the BAE apparatus, the more exactly this eigenstate is known. This near eigenstate, prepared by the first BAE, is then used as the input for a second BAE measurement, yielding a readout B. Correlations between readout A, readout B, and the transmitted signal demonstrate a true quantum nondemolition measurement of a known eigenstate of a quadrature component of the field.
| Original language | English |
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| Pages | 68 |
| Number of pages | 1 |
| State | Published - 1990 |
| Event | 17th International Conference on Quantum Electronics - IQEC '90 - Anaheim, CA, USA Duration: 21 May 1990 → 25 May 1990 |
Conference
| Conference | 17th International Conference on Quantum Electronics - IQEC '90 |
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| City | Anaheim, CA, USA |
| Period | 21/05/90 → 25/05/90 |