Neutral atoms put in charge

Abstract

An elegant experiment shows that atoms subjected to a pair of laser beams can behave like electrons in a magnetic field, as demonstrated by the appearance of quantized vortices in a neutral superfluid.Ultracold gases of atoms -a million times thinner than air and a million times colder than interstellar space -allow the observation and control of many-body quantum physics at macroscopic scales. They can thus serve as model materials 1 for condensed-matter systems where such quantum behaviour dominates. From frictionless flow in superfluids to inhibited transport in insulators and from weakly to strongly interacting systems, an extreme variety of fundamental states of matter can be realized in ultracold atomic gases in real time and with the precision of atomic physics. But there seems to be one obvious limitation: atoms are neutral, a fact that in principle precludes the observation of a wealth of phenomena tied to the behaviour of charged particles, for example their behaviour in a magnetic field. On page 000 of this issue, Lin et al. 2 get round this problem and demonstrate in a striking fashion their ability to create synthetic magnetic fields for a neutral ultracold atomic system -A collective state of matter termed a Bose-Einstein condensate develops mini-tornadoes known as quantized vortices. velocity (blue arrows) does not rotate. b, If the water flows non-uniformly and in a different direction on one side of the paddle wheel from that on the other, the wheel rotates (green arrow). The flow pattern is analogous to the 'vector potential' created in Lin and colleagues' experiment 2 to generate a synthetic magnetic field for an ultracold cloud of atoms known as a Bose-Einstein condensate. The rotation axis (purple arrow) and the speed with which the paddle wheel rotates correspond respectively to the direction and strength of the magnetic field. c, d, Images of the BoseEinstein condensate before (c) and after (d) application of the synthetic magnetic field. The appearance of quantized vortices (d) is a direct demonstration of a synthetic magnetic field.

Theoretical Approach of Differentiable–Non-Differentiable Scale Transition in Nanostructures

“…(14) implies Eq. (15) only in the condition of the supposition × V F = 0. Nottale's specific fractal potential, Q N , is obtained from (14) by means of relation Q N = Q/2 considering movements of the nanostructures entities on Peano type curve, D F = 2, and using the identifications = and D N = 2 / .…”

“…1 2-12 Fermionic condensate is an other example of quantum gas used to model the different phenomenon (i.e., superfluidity, superconductivity) in nanostructures. [13][14][15][16][17] But as is suggested by Gleick,18 all these models are about "being" not "becoming." In this paper we focus on process rather than state.…”

The non-Abelian bosonic quantum ring

“…Rotating the trap leads to a homogeneous effective magnetic field in the equation of motion of the gas in the rotating frame. A different approach uses optically induced effective magnetic fields which is a non-rotating setup where vortices [20,21,22,23,24] or solitons [25] can be created too. Without stirring or phase imprinting, vortex nucleation has also been observed in a mixing experiment of multiple trapped condensates [26].…”