Delayed choices in atom Stern-Gerlach interferometry

Abstract

Delayed-choice experiments have been performed using an atomic Stern-Gerlach interferometer operating with a low-intensity beam of metastable hydrogen atoms. By use of a fast-commutable analyzer, it is possible to modify the operating mode of the interferometer while the atom has already entered the device. Various types of delayed-choice experiments have been carried out to check the standard interpretation of quantummechanics. Within the experimental accuracy, our results do not show any discrepancy between permanent and delayed-choice operating modes of the interferometer. ͓S1050-2947͑96͒00712-3͔

Realistic interpretation of quantum mechanics and encounter-delayed-choice experiment

“…The wave-particle duality is a central concept of quantum mechanics and is strikingly illustrated in the well-known Wheeler's delayed-choice gedanken experiment [1][2][3][4][5][6][7][8][9]. A good demonstration of the delayed-choice experiment is given by a two-path interferometer, Mach-Zehnder interferometer (MZI), seen in Figure 1(a).…”

“…In the EDC experiment, the front parts of wave functions before the beam splitter insertion do not interfere and show the particle nature, and the back parts of the wave functions will interfere and show a wave nature. The predicted phenomenon is clearly demonstrated in the experiment, and supports the REIN idea.PACS numbers: 03.65.Ta, 03.65.Ud, 42.50.Xa,42.50.DvThe wave-particle duality is a central concept of quantum mechanics and is strikingly illustrated in the well-known Wheeler's delayed-choice gedanken experiment [1][2][3][4][5][6][7][8][9]. A good demonstration of the delayed-choice experiment is given by a two-path interferometer, Mach-Zehnder interferometer (MZI), seen in Figure 1(a).…”

"Experimental realization of Wheeler's delayed-choice Gedanken Experiment"

“…"Thus one decides the photon shall have come by one route or by both routes after it has already done its travel" (7). Since Wheeler's proposal, several pioneering delayed-choice experiments have been reported (10,11,12,13,14,15). However, none of them fully followed the original scheme, demanding to use single-particle quantum state and to achieve space-like separation between the choice of the performed measurement and the entering of the particle into the interferometer.…”

Fast metastable hydrogen atoms from H2molecules: twin atoms

“…Since the metastable 2s state of atomic hydrogen has a very long (122 ms) natural lifetime, the possibility of a fragmentation channel of H 2 into a pair of such metastable atoms would be perfectly suited for experiments, where manipulation of phase factors and the use of Stern-Gerlach interferometric techniques [10] is pursued, including time selection of events [11], delayed choice experiments [12] or double atom interferometry related to the quantum Zeno effect [13]. On the other hand, H 2 is the simplest neutral molecule, since it is made up of only four bodies.…”