Remarkable Interference Patterns

M. Sekulić

Bihui Zhu, Shujuan Liu, Hong-Wei Xiong

The interference pattern of two Bose—Einstein condensates released from a double-well potential for different holding times is theoretically investigated using a decoupled two-mode Bose—Hubbard model. For two coherently separated condensates, the interference displays a periodic behavior, which is closely related to the atomic interaction. A remarkable parity effect is found in the interference patterns. For certain holding times, the even/odd total number of atoms would result in different interference fringes. The influences of different initial conditions on the evolution of interference and the observation of parity effects are discussed.

Jerry B. Marion, Mark A. Heald

Yan-Hong Qin, Yong Wu, Li-Chen Zhao +1 more

Wave properties of solitons in a two-component Bose–Einstein condensate are investigated in detail. We demonstrate that dark solitons in one of components admit interference and tunneling behavior, in sharp contrast to the scalar dark solitons and vector dark solitons. Analytic analyses of interference properties show that spatial interference patterns are determined by the relative velocity of solitons, while temporal interference patterns depend on the velocities and widths of two solitons, differing from the interference properties of scalar bright solitons. Especially, for an attractive interactions system, we show that interference effects between the two dark solitons can induce some short-time density humps (whose densities are higher than background density). Moreover, the maximum hump value is remarkably sensitive to the variation of the solitons’ parameters. For a repulsive interactions system, the temporal-spatial interference periods of dark–bright solitons have lower limits. Numerical simulation results suggest that interference patterns for the dark–bright solitons are more robust against noises than bright–dark solitons. These explicit interference properties can be used to measure the velocities and widths of solitons. It is expected that these interference behaviors can be observed experimentally and can be used to design matter wave soliton interferometer in vector systems.

Giovanni Giusfredi

Dan Liu, Yichun Gao, Jianqin Xu +1 more

Inspired by a recent experiment [Phys. Rev. Lett. 122 253201(2019)] that an unprecedented quantum interference was observed in the way of stimulated Raman adiabatic passage (STIRAP) due to the coexisting resonant- and detuned-STIRAPs, we comprehensively study this effect. Our results uncover the scheme robustness towards any external-field fluctuations coming from laser intensity noise and imperfect resonance condition, as well as the persistence of high-contrast interference pattern even when more nearby excited levels are involved. We verify that an auxiliary dynamical phase accumulated in hold time caused by the presence of the quasi-dark state in detuned-STIRAP can sensitively manipulate the visibility and frequency of the interference pattern, representing a new hallmark to measure the hyperfine energy accurately. The robust stability of the scheme comes from the intrinsic superiority embedded in the STIRAP mechanism that preserves the coherence of population transfer, which promises a remarkable performance of quantum interference in a practical implementation.