Antibunching
Under antibunching the existence is a sub-Poisson statistics understood. The idea that single quantum connected thereto is not (in bundles engl. But bunches) can be measured individually.
Antibunching occurs e.g. B. when measuring temporal correlations of quantum fields with intensity interferometers , so in quantum statistical measurements. The quantum fields can e.g. B. photon or electron fields. Antibunching arises e.g. B. when measuring photon fields with an occupied mode ("one photon") as well as with electron fields. The former is referred to as photon antibunching , while the second is referred to as fermion anti-bunching.
Since electrons are fermions , two electrons can never be detected in the same place at the same time. Photons are bosons , in the photon can therefore antibunching a photon field be concluded that the emitter generates single photons (s. Single-photon source ). If several modes of the photon field were occupied, photon bunching could be measured on the basis of the boson character , which corresponds to a super Poisson statistic .
As can be seen from the names, a Poisson statistic is set as the normal for a statistic measurement , which is associated with a certain state of the quantum field and has minimal variance (in the sense of Heisenberg's uncertainty relation ). Fields of other variances are compared with this normal.
literature
- T. Jeltes, JM McNamara, W. Hogervorst, W. Vassen, V. Krachmalnicoff, M. Schellekens, A. Perrin, H. Chang, D. Boiron, A. Aspect & CI Westbrook: Comparison of the Hanbury Brown-Twiss effect for bosons and fermions . In: Nature . 445, 2007, pp. 402-405. doi : 10.1038 / nature05513 .