We demonstrate an atomic interferometer in which the atom passes through a single-zone optical beam consisting of a pair of bichromatic counterpropagating fields. During the passage, the atomic wave packets in two distinct internal states trace out split trajectories, guided by the optical beams, with the amplitude and spread of each wave packet varying continuously, producing fringes that can ...

We study the composition of time-frequency localization operators (wavepacket operators) and develop a symbolic calculus of such operators on modulation spaces. The use of time-frequency methods (phase space methods) allows the use of rough symbols of ultra-rapid growth in place of smooth symbols in the standard classes. As the main application it is shown that, in general, a localization opera...

We consider the stable dependence of solutions to wave equations on metrics in C class. The main result states that solutions depend uniformly continuously on the metric, when the Cauchy data is given in a range of Sobolev spaces. The proof is constructive and uses the wave packet approach to hyperbolic equations.

We discuss four general features of the force-free evolution of wave packets: 1 The spatial spread of a packet changes with time in a simple way. 2 For sufficiently short durations related to the spread in the momentum of the packet the probability distribution will move with uniform speed and little change in shape. 3 After a sufficiently long time related to the initial spatial spread the wav...

General arguments in favor of the necessity of a wave packet description of neutrino oscillations are presented, drawing from analogies with other wave phenomena. We present a wave packet description of neutrino oscillations in stationary beams using the density matrix formalism. Recent claims of the necessity of an equal energy of different massive neutrinos are refuted.

In the Majorana equation for particles with arbitrary spin, the wave packet is due not only to the uncertainty affecting position and momentum but also to the infinite components with decreasing mass forming the Majorana spinor. In this paper we prove that such components contribute to increase the spreading of the wave packet. Moreover, as occurs in the time propagation of the Dirac wave packe...

We demonstrate an information hiding and retrieval scheme with the relative phases between states in a Rydberg wave packet acting as the bits of a data register. We use a terahertz half-cycle pulse (HCP) to transfer phase-encoded information from an optically accessible angular momentum manifold to another manifold which is not directly accessed by our laser pulses, effectively hiding the infor...

This paper deals with peristaltic flow of a Johnson–Segalman fluid in an asymmetric channel under long-wavelength and lowReynolds number considerations. The channel asymmetry is caused due to the peristaltic wave train on the walls having different amplitudes and phase. A series solution for small Weissenberg number is obtained for the stream function, axial velocity, axial pressure gradient an...

Here we propose an experimental set-up in which it is possible to obtain the entanglement of a two-mode Gaussian state, be it pure or mixed, using only simple linear optical measurement devices. After a proper unitary manipulation of the two-mode Gaussian state only number and purity measurements of just one of the modes suffice to give us a complete and exact knowledge of the state’s entanglem...