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

11 Aug 2008

Volume 93, Issue 6, Articles (06xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 93, 062101 (2008); http://dx.doi.org/10.1063/1.2968206 (3 pages)

K. Shibata and K. Hirakawa
Enlarge Image | Read More
Page 1 of 4 Pages Next Page | Jump to Page
back to top
RSS Feeds

Enhanced nonresonant optical pumping based on turnstile transport in a chaotic microcavity laser

Juhee Yang, Sang-Bum Lee, Jeong-Bo Shim, Songky Moon, Soo-Young Lee, Sang Wook Kim, Jai-Hyung Lee, and Kyungwon An

Appl. Phys. Lett. 93, 061101 (2008); http://dx.doi.org/10.1063/1.2968210 (3 pages) | Cited 3 times

Online Publication Date: 11 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report efficient nonresonant optical pumping based on turnstile transport in a chaotic microcavity laser. We observed more than tenfold enhancement in the pumping efficiency at a particular pumping angle and at a particular boundary position of the microcavity while these angle and position are consistent with the turnstile transport mechanism in chaotic ray dynamics. The pumping efficiency distribution resembles that of the output emission for the same cavity, supporting the concept of time-reversed ray transport.
Show PACS
42.55.Sa Microcavity and microdisk lasers

Polarization-independent extraordinary optical transmission in one-dimensional metallic gratings with broad slits

Yuehui Lu, Min Hyung Cho, YoungPak Lee, and Joo Yull Rhee

Appl. Phys. Lett. 93, 061102 (2008); http://dx.doi.org/10.1063/1.2970959 (3 pages) | Cited 8 times

Online Publication Date: 12 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Extraordinary optical transmission (EOT) is achievable for transverse-magnetic polarization in one-dimensional metallic gratings with very narrow slits due to the excitation of coupled surface plasmon polaritons (SPPs). In contrast, SPP-produced EOT for transverse-electric (TE) polarized light is impossible because of the absence of SPPs for this polarization. However, TE-polarized EOT produced by trapped modes has been demonstrated. In this work, we reanalyze this phenomenon and apply it to gratings with broad slits (still in subwavelength) without the need for a specific dielectric filler in the grooves. The design proposed in this work simplifies and makes more practical the realization of gratings that possess polarization-independent EOT.
Show PACS
42.79.Dj Gratings

Bulletlike light pulses in photonic crystals

Chuanhong Zhou, Qian Gong, Peijun Yao, Deyin Zhao, and Xunya Jiang

Appl. Phys. Lett. 93, 061103 (2008); http://dx.doi.org/10.1063/1.2968938 (3 pages) | Cited 2 times

Online Publication Date: 12 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report the bulletlike propagation of light pulse in a particularly designed two-dimensional (2D) photonic crystal. Unlike traditional light bullet supported by nonlinear materials, this bulletlike propagation is achieved only by 2D photonic crystal, where the diffraction and the group velocity dispersion of a light pulse are eliminated naturally by combining two distinct properties of photonic crystal, i.e., self-collimation and zero group velocity dispersion. Moreover, we studied the influence of third order dispersion on the propagation of light bullet and found that it can be greatly suppressed by an improved structure of photonic crystal.
Show PACS
42.70.Qs Photonic bandgap materials

Low threshold electrically pumped quantum dot-micropillar lasers

S. Reitzenstein, T. Heindel, C. Kistner, A. Rahimi-Iman, C. Schneider, S. Höfling, and A. Forchel

Appl. Phys. Lett. 93, 061104 (2008); http://dx.doi.org/10.1063/1.2969397 (3 pages) | Cited 29 times

Online Publication Date: 12 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on low threshold lasing in electrically pumped quantum dot-micropillar cavities. Lasing action associated with threshold currents as low as 8 μA at 10 K is observed for micropillar cavities with quality factors exceeding 10.000. Due to an optimized contact scheme lasing is achieved for pillar structures with diameters as small as 1.5 μm, containing on average less than 100 quantum dots in the active layer. The transition from spontaneous to stimulated emission is confirmed by autocorrelation measurements which reveal pronounced photon bunching near threshold.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.60.Da Resonators, cavities, amplifiers, arrays, and rings

Local versus global absorption in thin-film solar cells with randomly textured surfaces

C. Rockstuhl, S. Fahr, F. Lederer, K. Bittkau, T. Beckers, and R. Carius

Appl. Phys. Lett. 93, 061105 (2008); http://dx.doi.org/10.1063/1.2965117 (3 pages) | Cited 30 times

Online Publication Date: 12 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Enhanced light absorption in amorphous silicon thin films deposited on randomly textured zinc-oxide surfaces is investigated by means of a rigorous diffraction theory taking into account measured surface profiles and near-field optical data. Global absorption enhancement is obtained in the calculations for particular modifications of the random texture. We furthermore spatially resolve local domains of the surface texture, which show the strongest contribution to the absorption. Criteria on how random surfaces should look like to enhance absorption in thin-film solar cells are derived.
Show PACS
84.60.Jt Photoelectric conversion
42.79.Wc Optical coatings

Fano filters based on transferred silicon nanomembranes on plastic substrates

Zexuan Qiang, Hongjun Yang, Li Chen, Huiqing Pang, Zhenqiang Ma, and Weidong Zhou

Appl. Phys. Lett. 93, 061106 (2008); http://dx.doi.org/10.1063/1.2971199 (3 pages) | Cited 21 times

Online Publication Date: 13 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report here the characteristics of surface-normal optical filters based on Fano resonances on patterned single crystalline silicon nanomembranes (SiNMs), which were fabricated and transferred onto transparent plastic substrates using a SiNM wet transfer process. Detailed experimental and theoretical analyses were carried out on the angular- and polarization-dependent transmission properties. The filter transmission is independent of the incident beam polarization under surface-normal conditions. Angle-independent transmission was observed for specific Fano resonances with certain polarizations. The measured angle-dependent transmission agrees well with the simulated transmission and dispersion properties based on the propagation wave-vector analysis.
Show PACS
42.79.Ci Filters, zone plates, and polarizers
81.07.Bc Nanocrystalline materials
42.70.Qs Photonic bandgap materials

Ultralow-power all-optical wavelength conversion in a silicon-on-insulator waveguide based on a heterogeneously integrated III-V microdisk laser

Liu Liu, Joris Van Campenhout, Günther Roelkens, Dries Van Thourhout, Pedro Rojo-Romeo, Philippe Regreny, Christian Seassal, Jean-Marc Fédéli, and Roel Baets

Appl. Phys. Lett. 93, 061107 (2008); http://dx.doi.org/10.1063/1.2967338 (3 pages) | Cited 7 times

Online Publication Date: 13 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Ultralow-power all-optical wavelength conversion is presented for a silicon-on-insulator wire waveguide with a heterogeneously integrated III-V microdisk laser. The principle relies on the suppression of natural lasing from the microdisk laser by an external injection. No probe beam is needed in this configuration. Static wavelength conversion with a control power of 6.4 μW or even lower is achieved. The resonance and gain provided by the microdisk cavity are at the origin of such low control power. Dynamically, wavelength conversion using a 5 Gbps non-return-to-zero bit sequence is demonstrated in the proposed device.
Show PACS
42.82.Et Waveguides, couplers, and arrays
42.55.Px Semiconductor lasers; laser diodes
42.60.By Design of specific laser systems
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation

Near-field analysis of surface electromagnetic waves in the bandgap region of a polymeric grating written on a one-dimensional photonic crystal

Tristan Sfez, Emiliano Descrovi, Lorenzo Dominici, Wataru Nakagawa, Francesco Michelotti, Fabrizio Giorgis, and Hans-Peter Herzig

Appl. Phys. Lett. 93, 061108 (2008); http://dx.doi.org/10.1063/1.2970961 (3 pages) | Cited 6 times

Online Publication Date: 14 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The spatial distribution of surface electromagnetic waves on a one-dimensional photonic crystal with a polymeric grating on top is mapped using a multiheterodyne scanning near-field optical microscope. The grating opens a bandgap. At the band edges, a stationary field formed by two surface waves with opposite propagation constants and almost identical amplitudes is produced. Field intensity maxima are localized to the grating peaks or grooves, depending on the wavelength. Far from the bandgap, we identify surface waves coupled via either the 0 or the −1 order of the grating. The corresponding phase profiles indicate that these waves propagate in opposite directions.
Show PACS
73.20.Mf Collective excitations (including excitons, polarons, plasmons and other charge-density excitations)
71.20.Rv Polymers and organic compounds
42.70.Qs Photonic bandgap materials

Laser pulse induced gold nanoparticle gratings

Wen-Chi Hung, Wood-Hi Cheng, Ming-Shan Tsai, Wei-Chih Chung, I-Min Jiang, and Pochi Yeh

Appl. Phys. Lett. 93, 061109 (2008); http://dx.doi.org/10.1063/1.2970988 (3 pages) | Cited 2 times

Online Publication Date: 14 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report the results of our experimental investigation of laser induced gold nanoparticle gratings and their optical diffraction properties. A single shot of a pair Nd-YAG laser pulses with the same polarization is directed toward a 6 nm thick gold film on a substrate of polymethyl methacrylate. As a result of the laser illumination, the thin gold film is fragmented into an array of nanoparticles. Through the observation of scanning electron and dark-field optical microscopes, we discovered that the morphology of the gold nanoparticle grating is dependent on the fluence of laser pulse. The spectrum of first order diffraction shows the dependence on the absorbance property due to the presence of the nanoparticles. The ablation of nanothickness thin films via the use of laser pulses may provide a simple and efficient method for the fabrication of nanoscale structures, including two dimensional arrays of nanoparticles.
Show PACS
42.79.Dj Gratings
52.38.Mf Laser ablation
42.86.+b Optical workshop techniques
42.70.-a Optical materials
42.62.-b Laser applications

Dynamics of ultraviolet emissions in Tm-doped AlN using above band gap excitation

N. Nepal, J. M. Zavada, D. S. Lee, and A. J. Steckl

Appl. Phys. Lett. 93, 061110 (2008); http://dx.doi.org/10.1063/1.2970993 (3 pages) | Cited 3 times

Online Publication Date: 14 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on dynamics of ultraviolet (UV) emissions using above band gap excitation in Tm-doped AlN epilayers grown by solid-source molecular beam epitaxy. The UV and visible photoluminescence (PL) spectra were measured using the frequency quadrupled output from a Ti:sapphire laser. In the UV region, dominant emissions at 298 and 358 nm were observed under 197 nm excitation. Temperature dependence of the PL intensities of these emission lines reveals a binding energy of ∼ 150 meV. The quenching of the UV emissions in AlN:Tm appears related to the thermal activation of the excitons bound to the rare-earth structured isovalent charge trap at 1.50 eV below the conduction band.
Show PACS
78.66.Fd III-V semiconductors
78.55.Cr III-V semiconductors
71.35.-y Excitons and related phenomena
71.15.Nc Total energy and cohesive energy calculations
71.20.Nr Semiconductor compounds

Electrically controlled silicon-based photonic crystal chromatic dispersion compensator with ultralow power consumption

Ching Eng Png, Gi Ho Park, Soon Thor Lim, Er Ping Li, Aaron J. Danner, Kensuke Ogawa, and Yong Tsong Tan

Appl. Phys. Lett. 93, 061111 (2008); http://dx.doi.org/10.1063/1.2971033 (3 pages) | Cited 5 times

Online Publication Date: 14 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We show full three-dimensional electrical and optical simulation of a tunable silicon-based photonic crystal chromatic dispersion compensator with high power efficiency and ultralow power consumption (114 nW), operating at a speed of 40.5 MHz. The device exploits a structure where the optical field maximum is not in a photonic crystal waveguide, but rather in a hybrid Si3N4/Si/SiO2 structure that will allow greater ease of fiber coupling due to larger mode size and reduced loss. The chromatic dispersion compensation is broadband and produces constant second order chromatic dispersion over an optical communication band such as C-band.
Show PACS
42.81.Qb Fiber waveguides, couplers, and arrays
42.82.Et Waveguides, couplers, and arrays
42.81.Dp Propagation, scattering, and losses; solitons
42.70.Qs Photonic bandgap materials
42.79.Sz Optical communication systems, multiplexers, and demultiplexers

Fabrication of periodic complex photonic crystals constructed with a portion of photonic quasicrystals by interference lithography

Yi Yang, Qiuze Li, and Guo Ping Wang

Appl. Phys. Lett. 93, 061112 (2008); http://dx.doi.org/10.1063/1.2969071 (3 pages) | Cited 3 times

Online Publication Date: 14 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
By using a single-beam optical interference lithography we fabricated a kind of periodic complex photonic crystals constructed with a portion of photonic quasicrystals. The periodic photonic crystals show the photonic bandgap properties of the original photonic quasicrystals but maintain the periodicity in long range so that their photonic band structures can exactly be calculated in theory. Diverse structures were fabricated by real time modulating the phase relation of the interference beams. The complex photonic crystal materials presented here may provide an example for creating diverse photonic structures for effectively manipulating electromagnetic properties.
Show PACS
42.82.Cr Fabrication techniques; lithography, pattern transfer
42.70.Qs Photonic bandgap materials
42.40.My Applications

Stabilized porous silicon optical superlattices with controlled surface passivation

M. Ghulinyan, B. Gelloz, T. Ohta, L. Pavesi, D. J. Lockwood, and N. Koshida

Appl. Phys. Lett. 93, 061113 (2008); http://dx.doi.org/10.1063/1.2969294 (3 pages) | Cited 7 times

Online Publication Date: 14 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on very effective stabilization of porous silicon optical devices through a chemical surface modification technique. Such a chemical treatment proves to alter the growth of native silicon oxide on pore surfaces and thus prevents the optical device from chemical aging. As an example, we apply this technique to one-dimensional freestanding optical superlattices made of five coupled microcavities. We demonstrate how the transmission resonances of the superlattice stabilize after treatment, which implies that refractive indices in the multilayer structure remain constant. The effectiveness of the chemical surface modification technique guarantees a long-life functionality of porous silicon-based optical devices.
Show PACS
42.70.-a Optical materials
81.65.Rv Passivation
78.67.Pt Multilayers; superlattices; photonic structures; metamaterials
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
81.05.Cy Elemental semiconductors

L-band ultrafast fiber laser mode locked by carbon nanotubes

Z. Sun, A. G. Rozhin, F. Wang, V. Scardaci, W. I. Milne, I. H. White, F. Hennrich, and A. C. Ferrari

Appl. Phys. Lett. 93, 061114 (2008); http://dx.doi.org/10.1063/1.2968661 (3 pages) | Cited 27 times

Online Publication Date: 15 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We fabricate a nanotube-polyvinyl alcohol saturable absorber with a broad absorption at 1.6 μm. We demonstrate a pulsed fiber laser working in the telecommunication L band by using this composite as a mode locker. This gives ∼ 498±16 fs pulses at 1601 nm with a 26.7 MHz repetition rate.
Show PACS
42.55.Wd Fiber lasers
42.60.By Design of specific laser systems
42.60.Fc Modulation, tuning, and mode locking
42.65.Re Ultrafast processes; optical pulse generation and pulse compression
42.79.Sz Optical communication systems, multiplexers, and demultiplexers

Thermal poling induced second-order nonlinearity in femtosecond-laser-modified fused silica

Honglin An, Simon Fleming, Benjamin W. McMillen, Kevin P. Chen, and David Snoke

Appl. Phys. Lett. 93, 061115 (2008); http://dx.doi.org/10.1063/1.2973149 (3 pages) | Cited 3 times

Online Publication Date: 15 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Thermal poling was utilized to induce second-order nonlinearity in regions of fused silica modified by 771 nm femtosecond laser pulses. With second-harmonic microscopy, it was found that the nonlinearity in the laser-modified region was much lower than that in nonmodified regions. This is attributed to a more rigid glass network after irradiation by the femtosecond laser pulses and/or lack of mobile alkali ions. Measurement of the distribution of chemical elements in the femtosecond-laser-modified region in a soda lime glass revealed a lower level of sodium ions.
Show PACS
42.70.Ce Glasses, quartz
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
42.65.Re Ultrafast processes; optical pulse generation and pulse compression
42.65.Ky Frequency conversion; harmonic generation, including higher-order harmonic generation
back to top
RSS Feeds

Noble gas retention in the target during rotating cylindrical magnetron sputtering

S. Mahieu, W. P. Leroy, D. Depla, S. Schreiber, and W. Möller

Appl. Phys. Lett. 93, 061501 (2008); http://dx.doi.org/10.1063/1.2970037 (3 pages) | Cited 8 times

Online Publication Date: 12 August 2008

Full Text: Read Online (HTML) | Download PDF


See Also: Erratum

Show Abstract
A rotating cylindrical magnetron with a Ti target was sputtered in pure Xe or in a mixture of Xe and N2. The atomic composition of the target surface during sputtering has been investigated by in situ Rutherford backscattering spectrometry. The noble gas atomic ratio at the target surface is around 3.4% or 9.8% for sputtering in pure Xe and with 10% N2 addition, respectively. Energy resolved mass spectrometry reveals that some of the implanted Xe atoms are sputtered from the target. A radiation enhanced diffusion/detrapping/sputtering mechanism is proposed to model the flux of noble gas leaving the target during sputtering.
Show PACS
79.20.Rf Atomic, molecular, and ion beam impact and interactions with surfaces
82.80.Yc Rutherford backscattering (RBS), and other methods of chemical analysis
82.80.Ms Mass spectrometry (including SIMS, multiphoton ionization and resonance ionization mass spectrometry, MALDI)
68.35.Dv Composition, segregation; defects and impurities
back to top
RSS Feeds

Radial breathing mode frequency of single-walled carbon nanotubes under strain

Tienchong Chang

Appl. Phys. Lett. 93, 061901 (2008); http://dx.doi.org/10.1063/1.2969033 (3 pages) | Cited 5 times

Online Publication Date: 11 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The radial breathing mode (RBM) frequency of a chiral single-walled carbon nanotube (SWCNT) under radial, axial, and torsional strain is investigated using a nonlinear stick-spiral model. It is shown that the normalized RBM frequency is strongly dependent on the tube chirality. The normalized RBM frequency of small tubes is also sensitive to the tube diameter, while for large tubes, the effect of tube diameter on the normalized RBM frequency is ignorable. The present findings are helpful to the understanding of strain dependent RBM frequency of a SWCNT.
Show PACS
63.22.Gh Nanotubes and nanowires
78.67.Ch Nanotubes
78.30.Na Fullerenes and related materials

Physical mechanisms of hydrogen-enhanced onset of epitaxial growth of silicon by plasma-enhanced chemical vapor deposition

X. Tan and G. W. Yang

Appl. Phys. Lett. 93, 061902 (2008); http://dx.doi.org/10.1063/1.2957674 (3 pages) | Cited 3 times

Online Publication Date: 11 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have theoretically performed the detailed physical process and the temperature dependence of the hydrogen-enhanced amorphous-to-crystalline transformation of silicon upon plasma-enhanced chemical vapor deposition (PECVD) using the kinetic Monte Carlo simulations. It is found that the epitaxial silicon can be obtained at very low temperatures (T ≥ 450 K) upon PECVD with H2 dilution. Our simulations have profound implications for closing the gap between atomic-scale and macroscopic measurements and gaining a full understanding of PECVD growth.
Show PACS
68.55.ag Semiconductors
81.05.Cy Elemental semiconductors
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
52.77.Dq Plasma-based ion implantation and deposition
64.70.kg Semiconductors

Influence of thermodynamics and local geometry on glass formation in Zr based alloys

P. K. Ray, K. Chattopadhyay, and B. S. Murty

Appl. Phys. Lett. 93, 061903 (2008); http://dx.doi.org/10.1063/1.2965116 (3 pages) | Cited 3 times

Online Publication Date: 11 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A theoretical approach for predicting glass forming ability of transition metal alloys is proposed. This is an attempt for synergistic understanding of the effects of thermodynamics and local geometry on glass forming ability. The enthalpy of formation has been estimated by a modified Miedema’s model and used as a criterion for stability. The lattice strain energy has been estimated by a modified Miracle’s model. The coordination numbers of the solute centered clusters have been used for establishing a set of inequalities that demarcate geometrically favored composition regimes. Glass formation within the geometrically favored areas is dictated by thermodynamics.
Show PACS
64.70.pe Metallic glasses
65.60.+a Thermal properties of amorphous solids and glasses: heat capacity, thermal expansion, etc.
82.60.Cx Enthalpies of combustion, reaction, and formation
61.43.Fs Glasses

Nanoscale amorphization at disclination quadrupoles in deformed nanomaterials and polycrystals

S. V. Bobylev and I. A. Ovid’ko

Appl. Phys. Lett. 93, 061904 (2008); http://dx.doi.org/10.1063/1.2953448 (3 pages) | Cited 2 times

Online Publication Date: 12 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Special micromechanism of nanoscale amorphization (crystal-to-glass transition in nanoscale regions) in deformed nano- and polycrystalline materials is suggested and theoretically described. The nanoscale amorphization occurs through transformation of disclination quadrupoles generated during plastic deformation. It is shown that the nanoscale amorphization at disclination quadrupoles is energetically favorable in nano- and polycrystalline Si and Si3N4 deformed at high applied stresses in certain ranges of their structural parameters.
Show PACS
64.70.Nd Structural transitions in nanoscale materials
62.25.-g Mechanical properties of nanoscale systems
61.46.-w Structure of nanoscale materials
62.20.F- Deformation and plasticity
61.72.Lk Linear defects: dislocations, disclinations
64.70.K- Solid-solid transitions

Femtosecond time-resolved x-ray diffraction from optical coherent phonons in CdTe(111) crystal

Kazutaka G. Nakamura, Satoshi Ishii, Shusei Ishitsu, Masato Shiokawa, Hiroshi Takahashi, Kurunthu Dharmalingam, Jun Irisawa, Yoichiro Hironaka, Kunie Ishioka, and Masahiro Kitajima

Appl. Phys. Lett. 93, 061905 (2008); http://dx.doi.org/10.1063/1.2968212 (3 pages) | Cited 6 times

Online Publication Date: 13 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Coherent phonons excited in a CdTe(111) crystal by 70 fs laser irradiation have been investigated by femtosecond time-resolved x-ray diffraction. The longitudinal optical phonon with a frequency of approximately 5 THz near the Brillouin zone center has been detected as modulation in intensities of x-ray diffraction. Atomic displacement in the [111] direction in the coherent longitudinal optical phonon has been estimated.
Show PACS
43.35.Gk Phonons in crystal lattices, quantum acoustics
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)

Formation and evolution of F nanobubbles in amorphous and crystalline Si

S. Boninelli, G. Impellizzeri, S. Mirabella, F. Priolo, E. Napolitani, N. Cherkashin, and F. Cristiano

Appl. Phys. Lett. 93, 061906 (2008); http://dx.doi.org/10.1063/1.2969055 (3 pages) | Cited 7 times

Online Publication Date: 13 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The formation and evolution of F-induced nanobubbles in Si was investigated. Si samples were preamorphized, implanted with F, and partially regrown by solid phase epitaxy (SPE). It is shown that nanobubbles are formed already in the amorphous side of partially regrown samples and are then incorporated in crystalline Si during SPE. The bubbles are interpreted as the result of the diffusion and coalescence of F atoms and dangling bonds already in the amorphous matrix. During high temperature annealing after SPE, F outdiffuses; correspondingly, the bubbles partially dissolve and transform from spherical- to cylinder-shaped bubbles.
Show PACS
85.40.Ry Impurity doping, diffusion and ion implantation technology
61.72.Qq Microscopic defects (voids, inclusions, etc.)

S passivation of GaAs and band bending reduction upon atomic layer deposition of HfO2/Al2O3 nanolaminates

F. S. Aguirre-Tostado, M. Milojevic, K. J. Choi, H. C. Kim, C. L. Hinkle, E. M. Vogel, J. Kim, T. Yang, Y. Xuan, P. D. Ye, and R. M. Wallace

Appl. Phys. Lett. 93, 061907 (2008); http://dx.doi.org/10.1063/1.2961003 (3 pages) | Cited 23 times

Online Publication Date: 13 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A systematic study of the interface engineering and dielectric properties of nanolaminated hafnium aluminate on GaAs is presented. The dielectrics were deposited using atomic layer deposition of alternating cycles of HfO2 and Al2O3 on GaAs substrates. High resolution x-ray photoelectron spectroscopy (XPS) showed differences in space charge amounts at the interface for the two surface treatments [NH4OH or (NH4)2S]. In-situ XPS analysis shows that chemical bonding to oxygen across the nanolaminate film is independent of the interface formation conditions. In addition, the GaAs surface treated with (NH4)2S shows a decreased band bending and slightly thinner films with respect to NH4OH.
Show PACS
77.55.-g Dielectric thin films
77.22.Ch Permittivity (dielectric function)
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.22.Jp Dielectric breakdown and space-charge effects
81.65.Rv Passivation
68.47.Fg Semiconductor surfaces

Size-dependent “malleable-to-brittle” transition in a bulk metallic glass

W. F. Wu, Z. Han, and Y. Li

Appl. Phys. Lett. 93, 061908 (2008); http://dx.doi.org/10.1063/1.2969784 (3 pages) | Cited 20 times

Online Publication Date: 13 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report a size-dependent malleability in a Zr-based bulk metallic glass (BMG) under both as-cast and annealed states. A “malleable-to-brittle” transition occurred at a critical sample size of 3 mm in diameter, below which the sample yielded with a consistent strength and above which the sample fractured in a brittle manner with decreasing strength. With minimization of the free volume effect by annealing, it was ascertained that this transition was due to the geometrical size effect rather than the free volume effect. The sharp decrease in strength for BMG within the brittle region was explained in terms of flaw sensitivity.
Show PACS
64.70.pe Metallic glasses
61.43.Fs Glasses
81.40.Gh Other heat and thermomechanical treatments

Atomic control and characterization of surface defect states of TiO2 terminated SrTiO3 single crystals

M. Kareev, S. Prosandeev, J. Liu, C. Gan, A. Kareev, J. W. Freeland, Min Xiao, and J. Chakhalian

Appl. Phys. Lett. 93, 061909 (2008); http://dx.doi.org/10.1063/1.2971035 (3 pages) | Cited 13 times

Online Publication Date: 14 August 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
By using an alternative wet-etch procedure, we have obtained high-quality atomically flat TiO2 terminated surfaces of SrTiO3 single crystals with the morphology equivalent to that of the conventional wet-etch methods. By applying a combined power of photoluminescence (PL) spectroscopy, reflection high-energy electron diffraction, atomic force microscopy imaging, and soft x-ray absorption (XAS), we were able to identify and monitor the complex evolution of oxygen defect states and Ti valency at the surface and near-surface layers. Our experiments revealed a high level of local defects resulting in the presence of the Ti3+ states at the surface. We have developed a method to control the defect states capable of a marked reduction of the defect concentration. We have demonstrated that the PL and XAS are able to distinguish the surface-related Ti3+ states from oxygen vacancies trapping charge transfer vibronic excitons that define the PL intensity. The experimental findings will have important implications for the growth of high-quality ultrathin complex oxide heterostructures.
Show PACS
61.72.jd Vacancies
73.20.-r Electron states at surfaces and interfaces
68.37.Ps Atomic force microscopy (AFM)
33.20.Rm X-ray spectra
78.70.Dm X-ray absorption spectra
78.55.Hx Other solid inorganic materials
Page 1 of 4 Pages Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close