Zobrazeno 1 - 10
of 16
pro vyhledávání: '"Lars M. Johansen"'
Autor:
Pier A. Mello, Lars M. Johansen
Publikováno v:
Physics Letters A. 372:5760-5764
We study successive measurements of two observables using von Neumann's measurement model. The two-pointer correlation for arbitrary coupling strength allows retrieving the initial system state. We recover Luders rule, the Wigner formula and the Kirk
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f8382c5d6c56333d1b91d68ae8089ae8
https://doi.org/10.1016/j.physleta.2008.07.021
https://doi.org/10.1016/j.physleta.2008.07.021
Autor:
Lars M. Johansen
Publikováno v:
Journal of Optics B: Quantum and Semiclassical Optics. 6:L21-L24
It is demonstrated that thermal radiation of small occupation number is strongly nonclassical. This includes most forms of naturally occurring radiation. Nonclassicality can be observed as a negative weak value of a positive observable. It is related
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c4f3a63cd638f6938e0ed833546547be
https://doi.org/10.1088/1464-4266/6/12/l01
https://doi.org/10.1088/1464-4266/6/12/l01
Autor:
Lars M. Johansen
Publikováno v:
Quantum Theory: A Two-Time Success Story ISBN: 9788847052161
Weak values are usually encountered in weak measurements on pre- and post-selected systems. Here we consider experiments where a final post-selection is replaced with an initial projector measurement. We show how weak values may be observed both for
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::b4cf43cc874241e2f921c32c49d61120
https://doi.org/10.1007/978-88-470-5217-8_19
https://doi.org/10.1007/978-88-470-5217-8_19
Autor:
Lars M. Johansen
Publikováno v:
Physics Letters A. 366:374-376
I propose a scheme for reconstructing the weak value of an observable without the need for weak measurements. The post-selection in weak measurements is replaced by an initial projector measurement. The observable can be measured using any form of in
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a3b67934dcff4734b05daeb01cc7785d
https://doi.org/10.1016/j.physleta.2007.02.039
https://doi.org/10.1016/j.physleta.2007.02.039
Autor:
Lars M. Johansen
Publikováno v:
Quantum Communication, Computing, and Measurement 2 ISBN: 0306463075
Lars M. Johansen
Lars M. Johansen
The density matrix of a nonrelativistic wave-packet in an arbitrary, one-dimensional and time-dependent potential can be reconstructed by measuring hydrodynamical moments of the Wigner distribution. An n-th order Taylor polynomial in the off-diagonal
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::3e3409f63ba3370cd61f7d7b9b24529e
https://doi.org/10.1103/physrevlett.80.5461
https://doi.org/10.1103/physrevlett.80.5461
Autor:
Lars M. Johansen
Publikováno v:
Physics Letters A. 236:173-176
It is shown that Bell's proof of violation of local realism in phase space is incorrect. Using Bell's approach, a violation can be derived also for nonnegative Wigner distributions. The error is found to lie in the use of an unnormalizable Wigner fun
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::7540289ac3f2bbabfab3ec4713e656d9
https://doi.org/10.1016/s0375-9601(97)00784-6
https://doi.org/10.1016/s0375-9601(97)00784-6
Autor:
Lars M. Johansen
Publikováno v:
Physical Review A. 56:100-107
A generalized form of the Einstein Podolsky-Rosen state is defined, embracing both classical and nonclassical states. It is shown that for such states, Bell's inequality is equivalent to a constraint on stochastic field theories. Thus violation of Be
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::d58cca7b64c4d9014fd8360bf38d7f2b
https://doi.org/10.1103/physreva.56.100
https://doi.org/10.1103/physreva.56.100
Autor:
Lars M. Johansen
Publikováno v:
Physics Letters A. 219:15-18
We show that no local, hidden variable model can be given for two-channel states exhibiting both a sufficiently high interference visibility and a sufficient degree of anticorrelation in a Mach-Zehnder interferometer.
4 pages, Revtex, 2 postscri
4 pages, Revtex, 2 postscri
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4f1056d03c9cbb811ad7e8fa4dca4349
https://doi.org/10.1016/0375-9601(96)00437-9
https://doi.org/10.1016/0375-9601(96)00437-9
Publikováno v:
AIP Conference Proceedings.
Many textbooks on Quantum Mechanics are not very precise as to the meaning of making a measurement: as a consequence, they frequently make assertions which are not based on a dynamical description of the measurement process. A model proposed by von N
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::001337739e32feb481f5075f4caaa461
https://doi.org/10.1063/1.3536611
https://doi.org/10.1063/1.3536611
Autor:
Lars M. Johansen
Publikováno v:
Physical Review A. 76
We show that a quantum state may be represented as the sum of a joint probability and a complex quantum modification term. The joint probability and the modification term can both be observed in successive projective measurements. The complex modific
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b0fba7f8cc43809445dde8f6b290d0ae
https://doi.org/10.1103/physreva.76.012119
https://doi.org/10.1103/physreva.76.012119