APL Nameplate
  • Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 

Flickr Twitter iResearch App Facebook

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue Next Issue

24 Sep 2001

Volume 79, Issue 13, pp. 1933-2115

Return to All Sections
back to top
RSS Feeds

Asymmetry diffraction magneto-optical phenomenon of NiFe grating

Y. T. Shen, Y. H. Wu, T. C. Chong, H. Xie, Z. B. Guo, K. B. Li, and J. J. Qiu

Appl. Phys. Lett. 79, 2034 (2001); http://dx.doi.org/10.1063/1.1404126 (3 pages) | Cited 3 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report the asymmetry of longitudinal magneto-optical Kerr loops obtained from diffracted spots of a NiFe grating. The analysis of several series of diffracted Kerr hysteresis loops reveals that the unsaturated magnetic structure not only contributes to the shape change of Kerr loops, but also results in asymmetric feature of Kerr loops because of the nonzero value of second-order magnetic response. A suitable pattern dimension, which defines the form factor, is helpful to observe asymmetry Kerr loops. Our experiment indicates that out-of-incidence-plane diffraction may offer an alternative method to observe lateral edge domain movements in patterns. © 2001 American Institute of Physics.
Show PACS
42.79.Dj Gratings
78.20.Ls Magneto-optical effects
42.30.Kq Fourier optics
75.60.Ch Domain walls and domain structure

Electron energy-loss spectroscopy study of a (LaMnO3)8(SrMnO3)4 heterostructure

J. Verbeeck, O. I. Lebedev, G. Van Tendeloo, J. Silcox, B. Mercey, M. Hervieu, and A. M. Haghiri-Gosnet

Appl. Phys. Lett. 79, 2037 (2001); http://dx.doi.org/10.1063/1.1403316 (3 pages) | Cited 9 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
An epitaxially grown heterostructure consisting of alternating layers of LaMnO3 (8 unit cells) and SrMnO3 (4 unit cells) on a SrTiO3 substrate has been studied by a combination of electron energy-loss spectroscopy (EELS) and high-resolution transmission electron microscopy (HRTEM) on an atomic scale. Excitation edges of all elements are captured with subnanometer spatial accuracy, and parametrized to obtain chemical profiles. The fine-edge structure of O K and Mn L2,3 edges are interpreted as signatures of the local electronic structure and show a spatial modulation of the concentration of holes with O 2p character. The chemical concentration is found to be different for the bottom and top interface of a SrMnO3 layer. HRTEM complements the EELS results and confirms the asymmetry of the interfaces. © 2001 American Institute of Physics.
Show PACS
68.65.Cd Superlattices
79.20.Uv Electron energy loss spectroscopy

Large magnetocaloric effect in manganites with charge order

P. Sande, L. E. Hueso, D. R. Miguéns, J. Rivas, F. Rivadulla, and M. A. López-Quintela

Appl. Phys. Lett. 79, 2040 (2001); http://dx.doi.org/10.1063/1.1403317 (3 pages) | Cited 35 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this work, we report the magnetocaloric effect (∣ΔSM∣), around the charge/orbital ordering transition in the mixed valent manganite Nd0.5Sr0.5MnO3. The magnitude of ∣ΔSM∣ around this first-order transition is around three times larger than that obtained around the second-order transition (ferromagnetic-metallic-to-paramagnetic-insulator) in the same compound. Actually, the magnetocaloric response around the charge-order transition is comparable to pure Gd, the rare earth with the highest magnetocaloric effect. The possibility of an easy tuning of the charge-order transition temperatures in doped manganites opens a way of investigation materials usable in magnetic refrigerators. © 2001 American Institute of Physics.
Show PACS
75.30.Sg Magnetocaloric effect, magnetic cooling
75.30.Kz Magnetic phase boundaries (including classical and quantum magnetic transitions, metamagnetism, etc.)
71.45.-d Collective effects

Effect of perimeters of induced shielding current loops on levitation force in melt grown single-domain YBa2Cu3O7−x bulk

W. M. Yang, L. Zhou, Y. Feng, P. X. Zhang, C. P. Zhang, Z. M. Yu, and X. D. Tang

Appl. Phys. Lett. 79, 2043 (2001); http://dx.doi.org/10.1063/1.1404999 (3 pages) | Cited 5 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Effects of perimeters of induced shielding current loops (ISCL) on a levitation force have been investigated for a single-domain YBa2Cu3O7−x sample. The sample was prepared by a top-seeded melt–growth process. The levitation force of the sample decreases monotonously with the increasing perimeters of ISCL while the depth of the cutting slot increases along its diameter from one side to another. The maximum levitation force of the sample without any cutting slot is about 1.68 times higher than that of the sample bisected. A simple physical model is afforded to interpret the experimental results. © 2001 American Institute of Physics.
Show PACS
74.72.-h Cuprate superconductors
74.25.Sv Critical currents
74.25.Uv Vortex phases (includes vortex lattices, vortex liquids, and vortex glasses)
74.25.Ha Magnetic properties including vortex structures and related phenomena

As-grown superconducting MgB2 thin films prepared by molecular beam epitaxy

Kenji Ueda and Michio Naito

Appl. Phys. Lett. 79, 2046 (2001); http://dx.doi.org/10.1063/1.1405421 (3 pages) | Cited 100 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Superconducting thin films of magnesium diboride (MgB2) were prepared on various substrates [SrTiO3 (001), sapphire R, sapphire C and Si (111)] by molecular beam epitaxy. The growth temperature was examined in the ambient to 650 °C. Only films formed at temperatures between 150 and 320 °C showed superconductivity. The best TConset of 36 K with a sharp transition width of ∼1 K was observed. The TC of the as-grown superconducting MgB2 thin films is close to the bulk value. © 2001 American Institute of Physics.
Show PACS
74.78.-w Superconducting films and low-dimensional structures
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
74.62.Bf Effects of material synthesis, crystal structure, and chemical composition
74.72.-h Cuprate superconductors
74.10.+v Occurrence, potential candidates
68.55.A- Nucleation and growth

Millisecond electron–phonon relaxation in ultrathin disordered metal films at millikelvin temperatures

M. E. Gershenson, D. Gong, T. Sato, B. S. Karasik, and A. V. Sergeev

Appl. Phys. Lett. 79, 2049 (2001); http://dx.doi.org/10.1063/1.1407302 (3 pages) | Cited 29 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have measured directly the thermal conductance between electrons and phonons in ultrathin Hf and Ti films at millikelvin temperatures. The experimental data indicate that electron–phonon coupling in these films is significantly suppressed by disorder. The electron cooling time τϵ follows the T−4 dependence with a record-long value τϵ = 25 ms at T = 0.04 K. The hot-electron detectors of far-infrared radiation, fabricated from such films, are expected to have a very high sensitivity. The noise-equivalent power of a detector with the area 1 μm2 and the noise limited by fluctuations of the temperature are expected to be (2–3)×10−20 W/math, which is two orders of magnitude smaller than that of the state-of-the-art bolometers. © 2001 American Institute of Physics.
Show PACS
73.61.At Metal and metallic alloys
71.38.-k Polarons and electron-phonon interactions
72.15.Eb Electrical and thermal conduction in crystalline metals and alloys
07.57.Kp Bolometers; infrared, submillimeter wave, microwave, and radiowave receivers and detectors
68.55.-a Thin film structure and morphology
85.60.Gz Photodetectors (including infrared and CCD detectors)
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close