Nikolay V. Vitanov

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This study examined the influence of sex, social dominance, and context on motion-tracked head movements during dyadic conversations. Windowed cross-correlation analyses found high peak correlation between conversants' head movements over short ( approximately 2-s) intervals and a high degree of nonstationarity. Nonstationarity in head movements was found(More)
We demonstrate experimental techniques for creating and measuring a coherent superposition of two degenerate atomic states with equal amplitudes in metastable neon. Starting from state (3)P(0), we create adiabatically a coherent superposition of the magnetic sublevels M=+/-1 of the state (3)P(2) using a tripod stimulated Raman adiabatic passage scheme. The(More)
A vital requirement for a quantum computer is the ability to locally address, with high fidelity, any of its qubits without affecting their neighbors. We propose an addressing method using composite sequences of laser pulses that dramatically reduces the addressing error in a lattice of closely spaced atoms or ions and at the same time significantly(More)
We present a method for optimization of the technique of adiabatic passage between two quantum states by composite sequences of frequency-chirped pulses with specific relative phases: composite adiabatic passage (CAP). By choosing the composite phases appropriately the nonadiabatic losses can be canceled to any desired order with sufficiently long(More)
We develop a theoretical description of photoassociative stimulated Raman adiabatic passage (STIRAP) near a Feshbach resonance in a thermal atomic gas. We show that it is possible to use low-intensity laser pulses to directly excite pairs of atoms in the continuum near a Feshbach resonance and to transfer most of the atomic cloud to the lowest rovibrational(More)
We examine theoretically the Casimir effect between a metallic plate and several types of magnetic metamaterials in pursuit of Casimir repulsion, by employing a rigorous multiple-scattering theory for the Casimir effect. We first examine metamaterials in the form of two-dimensional lattices of inherently nonmagnetic spheres such as spheres made from(More)
The first presentation of the STIRAP (stimulated Raman adiabatic passage) technique with proper theoretical foundation and convincing experimental data appeared 25 years ago, in the May 1st, 1990 issue of The Journal of Chemical Physics. By now, the STIRAP concept has been successfully applied in many different fields of physics, chemistry, and beyond. In(More)
We propose a novel setup for optically trapping neutral atoms based upon the focusing properties of metamaterials. The optical trap is created at the focal point of an inverted-opal crystal when the latter is illuminated by a localized light source. The trap is located away from the surface of the inverted-opal lens, rendering the Casimir-Polder attraction(More)
We propose an efficient, robust, and broadband nonlinear optical frequency conversion technique, which uses segmented crystals constructed in analogy with the composite pulses in nuclear magnetic resonance and quantum optics. The composite crystals are made of several macroscopic segments of nonlinear susceptibilities of opposite signs and specific(More)