Study for Reducing the Screening Current-Induced Field in a 10-MHz No-Insulation Magnet Using Current Sweep Reversal Method

Due to the high field enhancement factor and photon-absorption efficiency, carbon nanotubes (CNTs) have been widely used in optically induced field-emission as a cathode. Here, we report vertical carbon nanotube arrays (VCNTAs) that performed as high-density electron sources. A combination of high applied electric field and laser illumination made it possible to modulate the emission with laser pulses. When the bias electric field and laser power density increased, the emission process is sensitive to a power law of the laser intensity, which supports the emission mechanism of optically induced field emission followed by over-the-barrier emission. Furthermore, we determine a polarization dependence that exhibits a cosine behavior, which verifies the high possibility of optically induced field emission.

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Online correction of respiratory-induced field disturbances for continuous MR-thermometry in the breast

Magnetic Resonance in Medicine ◽

10.1002/mrm.21954 ◽

2009 ◽

Vol 61 (6) ◽

pp. 1494-1499 ◽

Cited By ~ 27

Author(s):

S. Hey ◽

G. Maclair ◽

B. D. de Senneville ◽

M. Lepetit-Coiffe ◽

Y. Berber ◽

...

Keyword(s):

Mr Thermometry ◽

Online Correction ◽

Induced Field

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Interactions of Ruddlesden-Popper Phases and Migration-Induced Field-Stabilized Polar Phase in Strontium Titanate

Crystals ◽

10.3390/cryst11060693 ◽

2021 ◽

Vol 11 (6) ◽

pp. 693

Author(s):

Christian Ludt ◽

Elena Ovchinnikova ◽

Anton Kulikov ◽

Dmitri Novikov ◽

Sibylle Gemming ◽

...

Keyword(s):

Strontium Titanate ◽

Density Functional ◽

Surface Region ◽

Point Of View ◽

Polar Phase ◽

Near Surface ◽

Atomic Displacements ◽

Induced Field ◽

And Migration ◽

Novel Concept

This work focuses on the validation of a possible connection of the known Ruddlesden-Popper (RP) phases and the novel concept of the migration-induced field-stabilized polar (MFP) phase. To study this subject, model structures of RP phases in bulk strontium titanate are analyzed by means of density functional theory (DFT). The obtained geometries are compared to experimental MFP data. Good agreement can be found concerning atomic displacements in the pm range and lattice strain inferred by the RP phases. Looking at the energy point of view, the defect structures are on the convex hull of the Gibb’s free energy. Although the dynamics to form the discussed defect models are not addressed in detail, the interplay and stability of the described defect model will add to the possible structure scenarios within the near-surface region of strontium titanate. As a result, it can be suggested that RP phases generally favor the MFP formation.

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