2,729 research outputs found
Localization of Bose-Einstein Condensation and Disappearance of Superfluidity of Strongly Correlated Bose Fluid in a Confined Potential
We develop a Bose fluid model in a confined potential to consider the new
quantum phase due to the localization of Bose-Einstein condensation and
disappearance of superfluidity which is recently observed in liquid 4He in
porous glass at high pressures. A critical pressure of the transition to this
phase can be defined by our new analytical criterion of supposing the size of
localized Bose-Einstein condensate becomes comparable to the scale of
confinement. The critical pressure is quantitatively consistent with
observations without free parameters.Comment: 2 pages, 1 figur
Quantized vortices in superfluid helium and atomic Bose-Einstein condensates
This article reviews recent developments in the physics of quantized vortices
in superfluid helium and atomic Bose-Einstein condensates. Quantized vortices
appear in low-temperature quantum condensed systems as the direct product of
Bose-Einstein condensation. Quantized vortices were first discovered in
superfluid 4He in the 1950s, and have since been studied with a primary focus
on the quantum hydrodynamics of this system. Since the discovery of superfluid
3He in 1972, quantized vortices characteristic of the anisotropic superfluid
have been studied theoretically and observed experimentally using rotating
cryostats. The realization of atomic Bose-Einstein condensation in 1995 has
opened new possibilities, because it became possible to control and directly
visualize condensates and quantized vortices. Historically, many ideas
developed in superfluid 4He and 3He have been imported to the field of cold
atoms and utilized effectively. Here, we review and summarize our current
understanding of quantized vortices, bridging superfluid helium and atomic
Bose-Einstein condensates. This review article begins with a basic
introduction, which is followed by discussion of modern topics such as quantum
turbulence and vortices in unusual cold atom condensates.Comment: 99 pages, 20 figures, Review articl
Electric Dipole Moments of Dyon and `Electron'
The electric and magnetic dipole moments of dyon fermions are calculated
within N=2 supersymmetric Yang-Mills theory including the theta-term. It is
found, in particular, that the gyroelectric ratio deviates from the canonical
value of 2 for the monopole fermion (n_m=1,n_e=0) in the case theta\not=0.
Then, applying the S-duality transformation to the result for the dyon
fermions, we obtain an explicit prediction for the electric dipole moment (EDM)
of the charged fermion (`electron'). It is thus seen that the approach
presented here provides a novel method for computing the EDM induced by the
theta-term.Comment: 16pages, no figures, PTPTeX, typos corrected, published versio
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