Near-field evidence for ferromagnetic "Nanoneedles" in Nd 1/2Sr 1/2MnO 3

Nano Letters

Volumn 7, Issue 6, 2007, Pages 1449-1453

  Kolb, Paul W ^a   Romero, Danilo B ^a   Drew, H Dennis ^a   Sushkov, Andrei B ^b   Ogale, Satish B ^c   Moritomo, Yutaka ^d  

^a LABORATORY FOR PHYSICAL SCIENCES   (United States)

^b University of Maryland   (United States)

^c NATIONAL CHEMICAL LABORATORY   (India)

^d UNIVERSITY OF TSUKUBA   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

CHARGE ORDERED INSULATORS (COI); MULTIPHASE COEXISTENCE;

FERROMAGNETIC MATERIALS; NANONEEDLES; NEAR FIELD SCANNING OPTICAL MICROSCOPY; NEODYMIUM COMPOUNDS; OPTICAL ANISOTROPY; PHASE TRANSITIONS;

SINGLE CRYSTALS;

NANOMATERIAL; NANOTUBE;

ARTICLE; CHEMISTRY; CONFORMATION; CRYSTALLIZATION; MACROMOLECULE; MAGNETISM; MATERIALS TESTING; METHODOLOGY; NANOTECHNOLOGY; PARTICLE SIZE; SURFACE PROPERTY; ULTRASTRUCTURE;

CRYSTALLIZATION; MACROMOLECULAR SUBSTANCES; MAGNETICS; MATERIALS TESTING; MOLECULAR CONFORMATION; NANOSTRUCTURES; NANOTECHNOLOGY; NANOTUBES; PARTICLE SIZE; SURFACE PROPERTIES;

EID: 34547308733     PISSN: 15306984     EISSN: None     Source Type: Journal    
DOI: 10.1021/nl0629761     Document Type: Article

References (13)

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11. z. Surface currents act to support the tangential H field. Higher conductivity allows metals to transmit this mode more effectively than insulators.
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13. In principle, the differences in bond lengths within the ab plane that give rise to optical anisotropy are temperature dependant. Additionally, the polarization used from scan to scan may not be the same because it was necessary to adjust the polarization with temperature to compensate for the temperature-dependant polarization rotation of fiber bends in the cryostat. Furthermore, the collection efficiency for a particular polarization was likely changing as a function of temperature. In general, the far-field collection efficiency of NSOM systems is dependant of the geometry of the collection system. In principle, the lens and parabolic mirror used in these experiments provides symmetric collection with no polarization sensitivity. In reality, the system demonstrates significant polarization sensitivity due to differences in focus, alignment, and orientation of the optical axes with the sample and asymmetric blocking of light in the optical path by the z-approach mechanism. In an alternative interpretation of the fading contrast, the FMM and COI phases mix uniformly and gradually with temperature. However, this picture is inconsistent with the results of the far-field imaging where regions of different phase are well demarcated.