We review the signal-to-noise properties of two setups for Correlation Plenoptic Imaging (CPI), a novel technique that exploits the correlations of light intensity to perform the typical tasks of plenoptic imaging: refocusing out-of- focus parts of the scene, extending the depth of field, reconstruct 3D objects, As opposed to first-order plenoptic imaging, based on direct intensity measurement, CPI does not entail a loss of spatial resolution. Both setups are based on the properties of chaotic light and employ the concept of ghost imaging in different ways: the first one to image the object, the second one to image the focusing element. We show that the SNR can be easier to control in the second CPI scheme, in which the object is focused by a lens.
We discuss three control strategies aimed at countering the effects of decoherence: the first hinges on frequent projective measurements, the second on frequent unitary "kicks" ("bang-bang" pulses) and the third on a strong continuous coupling. Decoherence is suppressed if the frequency N of the measurements/kicks is large enough or if the coupling K is sufficiently strong: in all these cases, the Hilbert space of the system splits into invariant subspaces, among which any transition is hindered. However, if N or K are large, but not extremely large, all these control procedures accelerate decoherence.
The time evolution of an unstable quantum system coupled with an external "measuring" apparatus is investigated. A quantum Zeno effect (hindered decay) or an inverse quantum Zeno effect (accelerated decay) may take place, depending on the features of the coupling and the response time of the apparatus. The transition between the two regimes is analyzed.
Conference Committee Involvement (1)
Noise and Information in Nanoelectronics, Sensors, and Standards III
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.