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

Flickr Twitter iResearch App Facebook

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue

28 Dec 2009

Volume 95, Issue 26, Articles (26xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 95, 261901 (2009); http://dx.doi.org/10.1063/1.3268436 (3 pages)

Weiqiang Wang, Richard Clark, Aiichiro Nakano, Rajiv K. Kalia, and Priya Vashishta
Enlarge Image | Read More
Page 2 of 4 Pages Previous Page Next Page | Jump to Page
back to top
RSS Feeds

Stress-enhancement in free-standing Si pillars through nonequilibrium dehydrogenation in SiN:H stress-liners by ultraviolet light irradiation

Takanori Tanaka, Taizoh Sadoh, Masashi Kurosawa, Masanori Tanaka, Masanori Yamaguchi, Shinji Suzuki, Tokuhide Kitamura, and Masanobu Miyao

Appl. Phys. Lett. 95, 262103 (2009); http://dx.doi.org/10.1063/1.3278596 (3 pages) | Cited 3 times

Online Publication Date: 28 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Tensile-strained Si pillars are desired to achieve three-dimensional (3D) transistors with high speed. Effects of ultraviolet (UV) light irradiation on tensile strains in Si pillars covered with SiN:H stress-liners are investigated as a function of the wavelength (172–436 nm). Tensile-stress enhancement is found at specific wavelengths (200–330 nm) under low-temperature heating (400 °C), where dehydrogenation in SiN:H is clearly detected by infrared absorption measurements. On the other hand, equilibrium dehydrogenation by high-temperature heating (>700 °C) without UV-irradiation does not cause tensile-stress enhancement. This nonequilibrium dehydrogenation at low temperatures opens up possibility of 3D transistors with high carrier mobility.
Show PACS
85.30.Tv Field effect devices
85.40.-e Microelectronics: LSI, VLSI, ULSI; integrated circuit fabrication technology
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
61.82.Fk Semiconductors

The origin of 2.78 eV emission and yellow coloration in bulk AlN substrates

A. Sedhain, L. Du, J. H. Edgar, J. Y. Lin, and H. X. Jiang

Appl. Phys. Lett. 95, 262104 (2009); http://dx.doi.org/10.1063/1.3276567 (3 pages) | Cited 4 times

Online Publication Date: 29 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The yellow color of bulk AlN crystals was found to be caused by the optical absorption of light with wavelengths shorter than that of yellow. This yellow impurity limits UV transparency and hence restricts the applications of AlN substrates for deep UV optoelectronic devices. Here, the optical properties of AlN epilayers, polycrystalline AlN, and bulk AlN single crystals have been investigated using photoluminescence (PL) spectroscopy to address the origin of this yellow appearance. An emission band with a linewidth of ∼ 0.3 eV (at 10 K) was observed at ∼ 2.78 eV. We propose that the origin of the yellow color in bulk AlN is due to a band-to-impurity absorption involving the excitation of electrons from the valence band to the doubly negative charged state, (VAl2−), of isolated aluminum vacancies, (VAl)3−/2− described by VAl2−+hν = VAl3−+h+. In such a context, the reverse process is responsible for the 2.78 eV PL emission.
Show PACS
78.55.Cr III-V semiconductors
68.47.Fg Semiconductor surfaces
78.66.Fd III-V semiconductors
68.55.ag Semiconductors
61.72.jd Vacancies
78.40.Fy Semiconductors

Plasma-assisted molecular beam epitaxy of high quality In2O3(001) thin films on Y-stabilized ZrO2(001) using In as an auto surfactant

Oliver Bierwagen, Mark E. White, Min-Ying Tsai, and James S. Speck

Appl. Phys. Lett. 95, 262105 (2009); http://dx.doi.org/10.1063/1.3276910 (3 pages) | Cited 11 times

Online Publication Date: 29 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The surface roughness of In2O3(001) films is a roadblock to potential semiconductor applications of this material. Using plasma-assisted molecular beam epitaxy we found that In2O3(001) films grow rough by the formation of {111} facets and In2O3(111) films grow smooth without facetting due to the conventionally used (oxygen-rich) conditions. This behavior indicates that the (111) surface is thermodynamically prefered over the (001) surface. We demonstrate that under indium-rich growth conditions these thermodynamics are changed allowing In2O3(001) films to grow smoothly without facetting. Surface indium plays a key role by acting as an auto surfactant that lowers the surface free energy difference between the (001) and the (111) surface.
Show PACS
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.55.ag Semiconductors
68.35.Md Surface thermodynamics, surface energies
65.40.gp Surface energy
81.05.Hd Other semiconductors
68.35.bg Semiconductors

Changes in VO2 band structure induced by charge localization and surface segregation

Changhong Chen and Zhaoyang Fan

Appl. Phys. Lett. 95, 262106 (2009); http://dx.doi.org/10.1063/1.3280375 (3 pages) | Cited 8 times

Online Publication Date: 30 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Vanadium vacancies introduce acceptor doping with hole localization, while oxygen vacancies cause electron localization and donor doping. As deposition temperature increases, donor concentration stays constant, whereas acceptor concentration significantly increases, leading to enhanced (011) lattice-plane compression and surface segregation. Localized charges result in shifts of O 1s and V4+ 2p core levels toward higher binding energies, and O 2p and V4+ 3d valence bands toward the Fermi level, but egπ bands lifting and a1g bands splitting energies are both insensitive to charge localization. Particularly, band-gap energy decreases with increasing V–V pair distance, and is significantly reduced by band tailing.
Show PACS
71.20.Ps Other inorganic compounds
61.72.sd Impurity concentration
71.55.Ht Other nonmetals
61.72.up Other materials
61.72.jd Vacancies
68.35.Dv Composition, segregation; defects and impurities
73.20.Fz Weak or Anderson localization

Morphology and defect properties of the Ge–GeO2 interface

L. Tsetseris and S. T. Pantelides

Appl. Phys. Lett. 95, 262107 (2009); http://dx.doi.org/10.1063/1.3280385 (3 pages) | Cited 13 times

Online Publication Date: 30 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Ge-based devices, currently being pursued as replacement of their Si counterparts, typically contain a germanium oxide layer next to the substrate. Here we show using first-principles calculations that, in contrast to Si technology, hydrogenation and fluorination are not effective ways of passivating Ge–GeO2 interfacial Pb centers with a Ge dangling bond (DB). Moreover, we identify DB geometries that differ from the Pb structures and we find that the Ge–GeO2 boundary has a higher atomic-scale roughness than the Si–SiO2 interface. These key differences in interface morphology and defect properties are consistent with experimental data.
Show PACS
68.35.Ct Interface structure and roughness
81.65.Rv Passivation
81.05.Cy Elemental semiconductors
73.20.Hb Impurity and defect levels; energy states of adsorbed species
71.55.Cn Elemental semiconductors
71.15.-m Methods of electronic structure calculations

High-field Hall effect and magnetoresistance in Fe3O4 epitaxial thin films up to 30 Tesla

A. Fernández-Pacheco, J. Orna, J. M. De Teresa, P. A. Algarabel, L. Morellon, J. A. Pardo, M. R. Ibarra, E. Kampert, and U. Zeitler

Appl. Phys. Lett. 95, 262108 (2009); http://dx.doi.org/10.1063/1.3276696 (3 pages) | Cited 8 times

Online Publication Date: 31 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have measured the Hall effect and the magnetoresistance of epitaxial Fe3O4 thin films grown on MgO (001) in magnetic fields up to 30 T. Using such high fields, it is possible to magnetically saturate films thicker than 40 nm, providing access to intrinsic conduction properties. We find an effective electron density corresponding to 1 electron per f.u. A smaller value is obtained for thinner films, caused by the increasing density of antiphase boundaries defects. The magnetoresistance is not saturating at 30 T, showing linear dependence at high fields, and peaks at the Verwey transition.
Show PACS
73.50.Jt Galvanomagnetic and other magnetotransport effects (including thermomagnetic effects)
71.30.+h Metal-insulator transitions and other electronic transitions
73.61.Ng Insulators

The effect of temperature on the secondary electron emission yield from single crystal and polycrystalline diamond surfaces

A. Stacey, S. Prawer, S. Rubanov, R. Ahkvlediani, Sh. Michaelson, and A. Hoffman

Appl. Phys. Lett. 95, 262109 (2009); http://dx.doi.org/10.1063/1.3275729 (3 pages)

Online Publication Date: 31 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The effect of temperature in the 293–473 K range, on the secondary electron emission (SEE) yield of single crystal and polycrystalline diamond film surfaces is reported. For the polycrystalline films the SEE yield was found to decay as function of electron irradiation dose while for the single crystal an increase occurs first, followed by a decrease. For both surfaces, the SEE yield increases significantly upon heating and obtained a nearly constant value with electron dose at 473 K. These effects are explained as due to the temperature dependence of the electron beam induced hydrogen desorption and surface band bending.
Show PACS
79.20.Hx Electron impact: secondary emission
81.40.Gh Other heat and thermomechanical treatments
61.80.Fe Electron and positron radiation effects
82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces
68.43.Nr Desorption kinetics

Role of germanium in the reduced temperature dependence of Ti-based nanocrystals formation for nonvolatile memory applications

Li-Wei Feng, Chun-Yen Chang, Ting-Chang Chang, Chun-Hao Tu, Pai-Syuan Wang, Yao-Feng Chang, Min-Chen Chen, and Hui-Chun Huang

Appl. Phys. Lett. 95, 262110 (2009); http://dx.doi.org/10.1063/1.3279131 (3 pages) | Cited 1 time

Online Publication Date: 31 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We investigated the physical and electrical characteristics of Ti-based nanocrystals (NCs) with composition of germanium fabricated by cosputtering titanium silicide and germanium targets for low temperature applications of nonvolatile memory. The addition of Ge significantly reduces the thermal budget necessary for Ti-based NCs formation to 500 °C in 2 min due to the rise of its morphological instability and agglomeration properties. Compositions characteristics were analyzed by x-ray photon-emission spectroscopy and formations of NCs were observed by transmission electron microscopy. Additionally, capacitance-voltage characteristics, data retention, and endurance properties are characterized to demonstrate its advantages for nonvolatile memory device applications.
Show PACS
61.46.Df Structure of nanocrystals and nanoparticles ("colloidal" quantum dots but not gate-isolated embedded quantum dots)
84.30.Sk Pulse and digital circuits
79.60.Bm Clean metal, semiconductor, and insulator surfaces
68.37.Lp Transmission electron microscopy (TEM)

Oxygen vacancies in N doped anatase TiO2: Experiment and first-principles calculations

Abdul K. Rumaiz, J. C. Woicik, E. Cockayne, H. Y. Lin, G. Hassnain Jaffari, and S. I. Shah

Appl. Phys. Lett. 95, 262111 (2009); http://dx.doi.org/10.1063/1.3272272 (3 pages) | Cited 27 times

Online Publication Date: 31 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have determined the electronic and atomic structure of N doped TiO2 using a combination of hard x-ray photoelectron spectroscopy and first-principles density functional theory calculations. Our results reveal that N doping of TiO2 leads to the formation of oxygen vacancies and the combination of both N impurity and oxygen vacancies accounts for the observed visible light catalytic behavior of N doped TiO2.
Show PACS
61.72.jd Vacancies
82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces
71.15.Mb Density functional theory, local density approximation, gradient and other corrections
61.72.up Other materials
79.60.-i Photoemission and photoelectron spectra

Influence of Si precursor on Ge segregation during ultrathin Si reduced pressure chemical vapor deposition on Ge

B. Vincent, W. Vandervorst, M. Caymax, and R. Loo

Appl. Phys. Lett. 95, 262112 (2009); http://dx.doi.org/10.1063/1.3280075 (3 pages) | Cited 2 times

Online Publication Date: 31 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This letter reports on the Ge segregation mechanism occurring during ultrathin (few monolayers) Si cap growth on Ge substrates by reduced pressure chemical vapor deposition. Thanks to extremely low energy secondary ion mass spectroscopy, we have highlighted that Ge segregation in Si-covered Ge does not depend on the growth temperature (in the 350–500 °C range) or on the carrier gas (H2,N2) used during Si growth. Solely the Si precursor used, i.e., the Si incorporation mechanism, impacts the Ge segregation rate. A multi-Ge segregation model is proposed, considering probabilities of sites exchanges in between all Si–Ge stacked atoms within the first nanometer of the layers.
Show PACS
64.75.Qr Phase separation and segregation in semiconductors
79.20.Rf Atomic, molecular, and ion beam impact and interactions with surfaces
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
68.55.ag Semiconductors

Resistive switching characteristics of ZnO thin film grown on stainless steel for flexible nonvolatile memory devices

Seunghyup Lee, Heejin Kim, Dong-Jin Yun, Shi-Woo Rhee, and Kijung Yong

Appl. Phys. Lett. 95, 262113 (2009); http://dx.doi.org/10.1063/1.3280864 (3 pages) | Cited 29 times

Online Publication Date: 31 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This paper reports a resistive switching device of Au/ZnO/stainless steel (SS) and its applicability as a flexible resistive random access memory (ReRAM). The Au/ZnO/SS structure was fabricated by radio frequency sputtering deposition of a ZnO thin film on the SS substrate. The fabricated device showed stable unipolar and bipolar resistive switching behaviors with reliable switching responses over 100 cycles. The device performance was not degraded upon bending, which indicates high potential for flexible ReRAM applications.
Show PACS
73.61.Ga II-VI semiconductors
81.15.Cd Deposition by sputtering
68.55.ag Semiconductors
73.40.Sx Metal-semiconductor-metal structures
84.30.Sk Pulse and digital circuits
back to top
RSS Feeds

The role of Zr and B in room temperature magnetic entropy change of FeZrB amorphous alloys

Yanyan Wang and Xiaofang Bi

Appl. Phys. Lett. 95, 262501 (2009); http://dx.doi.org/10.1063/1.3276558 (3 pages) | Cited 11 times

Online Publication Date: 28 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Effect of Zr and B on magnetocaloric effect for Fe90−xZr10Bx (x:3 ∼ 9) and Fe93−xZr7Bx (x:0 ∼ 13) amorphous alloys is presented. A clear dependence of peak magnetic entropy change (|ΔSmpk|) on (Zr+B) total contents rather than respective contents is observed and found to be correlated with average magnetic moment per Fe atom. Temperature of |ΔSmpk| corresponding to Curie temperature (Tc) is dependent on B contents, which is discussed in terms of exchange coupling. These findings exhibit in general the importance of Zr and B in seeking for an optimal |ΔSmpk| and meanwhile tunable Tc in Fe-based amorphous alloys.
Show PACS
75.30.Sg Magnetocaloric effect, magnetic cooling
65.60.+a Thermal properties of amorphous solids and glasses: heat capacity, thermal expansion, etc.
75.30.Kz Magnetic phase boundaries (including classical and quantum magnetic transitions, metamagnetism, etc.)
75.50.Kj Amorphous and quasicrystalline magnetic materials
75.30.Cr Saturation moments and magnetic susceptibilities

Direct measurements of the penetration depth in a superconducting film using magnetic force microscopy

E. Nazaretski, J. P. Thibodaux, I. Vekhter, L. Civale, J. D. Thompson, and R. Movshovich

Appl. Phys. Lett. 95, 262502 (2009); http://dx.doi.org/10.1063/1.3276563 (3 pages) | Cited 2 times

Online Publication Date: 28 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report the local measurements of the magnetic penetration depth λ in a superconducting Nb film using magnetic force microscopy (MFM). We developed a method for quantitative extraction of the penetration depth from single-parameter simultaneous fits to the lateral and height profiles of the MFM signal, and demonstrate that the obtained value is in excellent agreement with that obtained from the bulk magnetization measurements.
Show PACS
74.78.-w Superconducting films and low-dimensional structures
74.70.Ad Metals; alloys and binary compounds (including A15, MgB2, etc.)
74.25.Ha Magnetic properties including vortex structures and related phenomena
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects

Generation of local magnetic fields at megahertz rates for the study of domain wall propagation in magnetic nanowires

Bastiaan Bergman, Rai Moriya, Masamitsu Hayashi, Luc Thomas, Christy Tyberg, Yu Lu, Eric Joseph, Mary-Beth Rothwell, John Hummel, William J. Gallagher, Bert Koopmans, and Stuart S. P. Parkin

Appl. Phys. Lett. 95, 262503 (2009); http://dx.doi.org/10.1063/1.3265738 (3 pages) | Cited 1 time

Online Publication Date: 28 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We describe a technique for generating local magnetic fields at megahertz rates along magnetic nanowires. Local and global magnetic fields are generated from buried copper fine-pitch wires fabricated on 200 mm silicon wafers using standard complementary metal-oxide-semiconductor back-end process technology. In combination with pump-probe scanning Kerr microscopy, we measure the static and dynamic propagation fields of domain walls in permalloy nanowires.
Show PACS
75.60.Ch Domain walls and domain structure
75.50.Tt Fine-particle systems; nanocrystalline materials
81.16.-c Methods of micro- and nanofabrication and processing

Role of reversal incoherency in reducing switching field and switching field distribution of exchange coupled composite bit patterned media

T. Hauet, E. Dobisz, S. Florez, J. Park, B. Lengsfield, B. D. Terris, and O. Hellwig

Appl. Phys. Lett. 95, 262504 (2009); http://dx.doi.org/10.1063/1.3276911 (3 pages) | Cited 23 times

Online Publication Date: 29 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Model exchange coupled composite media, namely [Co/Pd]5/Pd(t)/[Co/Ni]3/Co multilayers, deposited onto prepatterned substrates have been investigated for potential use in bit patterned recording. Optimizing the thickness of the Pd interlayer allows decreasing the switching field (HC) and switching field distribution (σSFD) while maintaining thermal stability. The dependence of the remanent coercivity on the external field angle indicates that the gain in HC and σSFD originates from the incoherent magnetization reversal introduced by slightly decoupling the hard and soft multilayer stacks. This tendency is confirmed by further reductions in HC and σSFD, when inserting another Pd interlayer within the hard [Co/Pd]5 stack.
Show PACS
75.70.Cn Magnetic properties of interfaces (multilayers, superlattices, heterostructures)
75.30.Et Exchange and superexchange interactions
75.50.Ss Magnetic recording materials
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
75.60.Jk Magnetization reversal mechanisms

Phase-locking and frustration in an array of nonlinear spin-torque nano-oscillators

Vasil Tiberkevich, Andrei Slavin, Elena Bankowski, and Grant Gerhart

Appl. Phys. Lett. 95, 262505 (2009); http://dx.doi.org/10.1063/1.3278602 (3 pages) | Cited 7 times

Online Publication Date: 29 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We demonstrate that the cooperative dynamics of an array of coupled spin-torque nano-oscillators (STNO) can be controlled by introduction of an additional external phase shift βc between microwave current, which couples STNOs, and microwave voltage on the array. When this external phase shift βc compensates the intrinsic phase shift β0, caused by the STNO nonlinearity, a phase-locking regime with increased output power and vanishing inhomogeneous linewidth broadening is achieved. In the opposite case, when external and intrinsic phase shifts are added, the STNO array demonstrates a frustration regime with low output power and wide and noisy frequency spectrum.
Show PACS
84.40.Dc Microwave circuits
84.30.Ng Oscillators, pulse generators, and function generators

Co doped ZnO(0001)-Zn by diffusion method and its magnetic properties

W. G. Xie, F. Y. Xie, X. L. Yu, K. Xue, J. B. Xu, J. Chen, and R. Zhang

Appl. Phys. Lett. 95, 262506 (2009); http://dx.doi.org/10.1063/1.3275713 (3 pages) | Cited 5 times

Online Publication Date: 30 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The diffusion behaviors of Co clusters on clean ZnO(0001)-Zn single crystal surface and their magnetic properties are studied. Co clusters are deposited on the clean ZnO(0001)-Zn surface at room temperature and then undergone ultrahigh vacuum annealing until fully reconstructed. The replacement of Zn2+ by Co2+ is confirmed by scanning tunneling microscopy and x-ray photoelectron spectroscopy. The Co doped ZnO shows a weak ferromagnetism at room temperature with a saturation magnetic moment of 1.08 μB/Co. Our observations indicate that surface Zn vacancies facilitate Co diffusion, and the interplay of Co ion with internal O vacancies leads to the ferromagnetism.
Show PACS
81.05.Dz II-VI semiconductors
75.50.Pp Magnetic semiconductors
61.72.Cc Kinetics of defect formation and annealing
81.40.Gh Other heat and thermomechanical treatments
79.60.Bm Clean metal, semiconductor, and insulator surfaces
68.35.Fx Diffusion; interface formation
75.50.Dd Nonmetallic ferromagnetic materials
75.30.Cr Saturation moments and magnetic susceptibilities
61.72.jd Vacancies

Enhancement in transition temperature and upper critical field of CeO0.8F0.2FeAs by yttrium doping

J. Prakash, S. J. Singh, A. Banerjee, S. Patnaik, and A. K. Ganguli

Appl. Phys. Lett. 95, 262507 (2009); http://dx.doi.org/10.1063/1.3280046 (3 pages) | Cited 8 times

Online Publication Date: 30 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report significant enhancement in superconducting properties of yttrium substituted Ce1−xYxOFFeAs superconductors. The polycrystalline samples were prepared by two step solid state reaction technique. X-ray diffraction confirmed tetragonal ZrCuSiAs structure with decrease in both a and c lattice parameters on increasing yttrium substitution (with fixed F content). With smaller ion Y in place of Ce, the transition temperature increased by 6 K. Yttrium doping also lead to higher critical fields as well as broader magnetization loops, particularly at elevated temperature.
Show PACS
74.62.Dh Effects of crystal defects, doping and substitution
74.70.-b Superconducting materials other than cuprates
74.25.Ha Magnetic properties including vortex structures and related phenomena
61.66.Fn Inorganic compounds
81.20.-n Methods of materials synthesis and materials processing

Spin-wave propagation in a microstructured magnonic crystal

A. V. Chumak, P. Pirro, A. A. Serga, M. P. Kostylev, R. L. Stamps, H. Schultheiss, K. Vogt, S. J. Hermsdoerfer, B. Laegel, P. A. Beck, and B. Hillebrands

Appl. Phys. Lett. 95, 262508 (2009); http://dx.doi.org/10.1063/1.3279138 (3 pages) | Cited 18 times

Online Publication Date: 31 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Transmission of microwave spin waves through a microstructured magnonic crystal in the form of a Permalloy waveguide of a periodically varying width was studied experimentally and theoretically. The spin wave characteristics were measured by spatially resolved Brillouin light scattering microscopy. A rejection frequency band was clearly observed. The band gap frequency was controlled by the applied magnetic field. The measured spin-wave intensity as a function of frequency and propagation distance is in good agreement with a model calculation.
Show PACS
84.40.Az Waveguides, transmission lines, striplines
78.35.+c Brillouin and Rayleigh scattering; other light scattering
75.30.Ds Spin waves
42.70.Qs Photonic bandgap materials

Control of spin-wave phase and wavelength by electric current on the microscopic scale

Vladislav E. Demidov, Sergei Urazhdin, and Sergej O. Demokritov

Appl. Phys. Lett. 95, 262509 (2009); http://dx.doi.org/10.1063/1.3279152 (3 pages) | Cited 10 times

Online Publication Date: 31 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We demonstrate experimentally the ability to control by electric current the phase and the wavelength of spin waves propagating in submicrometer magnetic waveguides. The dependence of the spin-wave characteristics on the current and on the excitation frequency was determined by phase-resolved microfocus Brillouin light scattering spectroscopy. We show that moderately small currents are sufficient to induce nearly twofold changes of the wavelength and spin-wave phase shift of more than ±π radians over a propagation distance of several micrometers.
Show PACS
75.30.Ds Spin waves
75.40.Gb Dynamic properties (dynamic susceptibility, spin waves, spin diffusion, dynamic scaling, etc.)
78.35.+c Brillouin and Rayleigh scattering; other light scattering
back to top
RSS Feeds

Surface and size effects on phase diagrams of ferroelectric thin films

D. C. Ma, Yue Zheng, and C. H. Woo

Appl. Phys. Lett. 95, 262901 (2009); http://dx.doi.org/10.1063/1.3272942 (3 pages) | Cited 6 times

Online Publication Date: 28 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Taking into account effects of the surface and depolarization field, we investigated the “misfit strain-temperature” phase diagrams of ferroelectric thin film by using the time-dependent Ginzburg–Landau theory. The simulation results show that the surface effect can shift the phase diagram to lower temperature. More importantly, effect of the depolarization field obviously shrinks the c-phase, and dominates the paraelectric and aa-phase in the phase diagram.
Show PACS
81.30.Dz Phase diagrams of other materials
77.80.-e Ferroelectricity and antiferroelectricity

Electric-field-controlled directional motion of ferroelectric domain walls in multiferroic BiFeO3 films

T. H. Kim (김태헌), S. H. Baek, S. M. Yang, S. Y. Jang, D. Ortiz, T. K. Song, J.-S. Chung, C. B. Eom, T. W. Noh, and J.-G. Yoon

Appl. Phys. Lett. 95, 262902 (2009); http://dx.doi.org/10.1063/1.3275736 (3 pages) | Cited 8 times

Online Publication Date: 31 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We describe the directional ferroelectric domain wall motion in a multiferroic BiFeO3 thin film, which was grown epitaxially on a vicinal (001) SrTiO3 substrate. A structural analysis of the film shows that a strain gradient is developed in our film, which creates a symmetry breaking in a ferroelectric double-well potential. The asymmetric double-well potential can cause ferroelectric domain walls to move sideways with preferred directionality under a vertical electric field. Our results suggest the possibility of controlling the direction of domain growth with an electric field by imposing constraints on ferroelectric films, such as a strain gradient.
Show PACS
77.80.Dj Domain structure; hysteresis
77.55.fp Other ferroelectric films
77.84.Bw Elements, oxides, nitrides, borides, carbides, chalcogenides, etc.
75.85.+t Magnetoelectric effects, multiferroics
back to top
RSS Feeds

Ultrasound holography for noninvasive imaging of buried defects and interfaces for advanced interconnect architectures

Gajendra Shekhawat, Arvind Srivastava, Shraddha Avasthy, and Vinayak Dravid

Appl. Phys. Lett. 95, 263101 (2009); http://dx.doi.org/10.1063/1.3263716 (3 pages) | Cited 4 times

Online Publication Date: 28 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Imaging high resolution subsurface defects nondestructively in advanced interconnect structures and devices is a challenge and no known metrology tools are available to identify such defects in a nondestructive way at nanometer level. Monitoring these defects necessitate the understanding of their growth mechanism of these interconnects as well as defect formation. We report here the application of scanning near field ultrasound holography by imaging buried defects in copper interconnects and low-K dielectric materials. Defects in these copper lines such as voids and delaminations appear as regions of dark contrast in ultrasound holography imaging due to large acoustic impedance mismatch at the voids. Identification of these buried defects in these interconnect architectures in a nondestructive way will open up unique opportunities in using this technique to detect subsurface defects and material imperfections.
Show PACS
43.60.Sx
81.70.Cv Nondestructive testing: ultrasonic testing, photoacoustic testing
85.35.-p Nanoelectronic devices
85.40.Ls Metallization, contacts, interconnects; device isolation

Molecular beam epitaxy-grown Bi4Te3 nanowires

G. Wang, S. K. Lok, G. K. L. Wong, and I. K. Sou

Appl. Phys. Lett. 95, 263102 (2009); http://dx.doi.org/10.1063/1.3276071 (3 pages) | Cited 3 times

Online Publication Date: 28 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
With Au nanoparticles as the catalyst, the formation of Bi4Te3 nanowires was achieved at an optimized substrate temperature of around 330 °C. We found two growth mechanisms for the nanowires: a self-assembled growth mode through islands as the seed and a vapor-solid-solid growth mode through the assistance of Au catalyst nanoparticles, the decisive factor for which was identified as the density of the Au nanoparticles.
Show PACS
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.55.ag Semiconductors
81.16.Dn Self-assembly
61.46.Df Structure of nanocrystals and nanoparticles ("colloidal" quantum dots but not gate-isolated embedded quantum dots)
82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces

Magnetomotive drive and detection of clamped-clamped mechanical resonators in water

W. J. Venstra, H. J. R. Westra, K. Babaei Gavan, and H. S. J. van der Zant

Appl. Phys. Lett. 95, 263103 (2009); http://dx.doi.org/10.1063/1.3275014 (3 pages) | Cited 2 times

Online Publication Date: 29 December 2009

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We demonstrate magnetomotive drive and detection of doubly clamped string resonators in water. A compact 1.9 T permanent magnet is used to detect the fundamental and higher flexural modes of 200 μm long resonators. Good agreement is found between the magnetomotive measurements and optical measurements performed on the same resonator. The magnetomotive detection scheme can be used to simultaneously drive and detect multiple sensors or scanning probes in viscous fluids without alignment of detector beams.
Show PACS
07.10.Cm Micromechanical devices and systems
85.85.+j Micro- and nano-electromechanical systems (MEMS/NEMS) and devices
Page 2 of 4 Pages Previous Page Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close