Equilibrium state of planar arrays of magnetic dipoles in the presence of exchange interaction

Abstract Natural materials typically interact weakly with the magnetic component of light which greatly limits their applications. This has led to the development of artificial metamaterials and metasurfaces. However, natural atoms, where only electric dipole transitions are relevant at optical frequencies, can cooperatively respond to light to form collective excitations with strong magnetic, as well as electric, interactions together with corresponding electric and magnetic mirror reflection properties. By combining the electric and magnetic collective degrees of freedom, we show that ultrathin planar arrays of atoms can be utilized as atomic lenses to focus light to subwavelength spots at the diffraction limit, to steer light at different angles allowing for optical sorting, and as converters between different angular momentum states. The method is based on coherently superposing induced electric and magnetic dipoles to engineer a quantum nanophotonic Huygens’ surface of atoms, giving full 2π phase control over the transmission, with close to zero reflection.

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Some aspects of the defect structure in an austenitic stainless steel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108714 ◽

1978 ◽

Vol 36 (1) ◽

pp. 314-315

Author(s):

R. Gonzalez ◽

L. Bru

Keyword(s):

Stainless Steel ◽

Austenitic Stainless Steel ◽

Cellular Structures ◽

Total Strain Amplitude ◽

Total Deformation ◽

Density Of Dislocations ◽

Planar Arrays ◽

Stacking Fault Tetrahedra ◽

Distribution Of Dislocations ◽

Very High

The analysis of stacking fault tetrahedra (SFT) in fatigued metals (1,2) is somewhat complicated, due partly to their relatively low density, but principally to the presence of a very high density of dislocations which hides them. In order to overcome this second difficulty, we have used in this work an austenitic stainless steel that deforms in a planar mode and, as expected, examination of the substructure revealed planar arrays of dislocation dipoles rather than the cellular structures which appear both in single and polycrystals of cyclically deformed copper and silver. This more uniform distribution of dislocations allows a better identification of the SFT.The samples were fatigue deformed at the constant total strain amplitude Δε = 0.025 for 5 cycles at three temperatures: 85, 293 and 773 K. One of the samples was tensile strained with a total deformation of 3.5%.

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Electron-hole long-range exchange interaction in semiconductor quantum dots

Journal of Crystal Growth ◽

10.1016/s0022-0248(97)00671-4 ◽

1998 ◽

Vol 184-185 (1-2) ◽

pp. 393-397 ◽

Cited By ~ 1

Author(s):

S Goupalov

Keyword(s):

Quantum Dots ◽

Exchange Interaction ◽

Long Range ◽

Semiconductor Quantum Dots ◽

Electron Hole

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INDIRECT EXCHANGE INTERACTION IN Hg1-xMnxTe AND Cd1-xMnxTe ALLOYS

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1980549 ◽

1980 ◽

Vol 41 (C5) ◽

pp. C5-289-C5-292 ◽

Cited By ~ 12

Author(s):

C. Lewiner ◽

J. A. Gaj ◽

G. Bastard

Keyword(s):

Exchange Interaction ◽

Indirect Exchange Interaction ◽

Indirect Exchange

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A Hitherto Undescribed Naturally Occurring Plasma Antagonist of Activated Factor X Inhibitor (Antithrombin III)

10.1055/s-0038-1665828 ◽

1979 ◽

Author(s):

E. T. Yin ◽

W. J. Salsgiver ◽

O. Tangen

Keyword(s):

Equilibrium State ◽

Human Plasma ◽

Antithrombin Iii ◽

Circumstantial Evidence ◽

Incubation Mixture ◽

Factor X ◽

Normal Human Plasma ◽

Plasma Component ◽

Naturally Occurring ◽

Normal Human

Circumstantial evidence suggested that normal human plasma contained a substance regulating the neutralization of F.Xa by F.Xa inhibitor(XaI), (Yin et.al.,Adv.Exper. Med. & Biol., 52 : 239, 1975, Plenum Press, N.Y.).This plasma component has now been isolated and partially purified in our laboratory, and tentatively designated as “Anti-XaI”.In experiments employing purified components, when Anti-XaI was incubated at 37°C with F.Xa, Xal and heparin for two minutes at pH7.5, the amount of F.Xa inhibited was inversely proportional to the Anti-XaI concentration. But, when the F.Xa was replaced by thrombin in the incubation mixture, the neutralization of thrombin clotting activity was undisturbed.Anti-XaI was found to be neither PF3 nor PF4.These and other data strongly suggest that the “Antithrombin III pathway” is more complex than currently believed to be. In circulating blood an equilibrium state must exist between Anti-XaI and XaI.Under certain conditions when the Anti-XaI activity is predominant the rate of F.Xa neutralization bv XaI then becomes slower than the activation of prothrombin to thrombin by F.Xa.

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