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

Flickr Twitter iResearch App Facebook

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Next Issue

2 Jan 2012

Volume 100, Issue 1, Articles (01xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 100, 013101 (2012); http://dx.doi.org/10.1063/1.3673334 (3 pages)

Patrice Genevet, Nanfang Yu, Francesco Aieta, Jiao Lin, Mikhail A. Kats, Romain Blanchard, Marlan O. Scully, Zeno Gaburro, and Federico Capasso
Enlarge Image | Read More
Return to All Sections
back to top
RSS Feeds
FREE

Ultra-thin plasmonic optical vortex plate based on phase discontinuities

Patrice Genevet, Nanfang Yu, Francesco Aieta, Jiao Lin, Mikhail A. Kats, Romain Blanchard, Marlan O. Scully, Zeno Gaburro, and Federico Capasso

Appl. Phys. Lett. 100, 013101 (2012); http://dx.doi.org/10.1063/1.3673334 (3 pages) | Cited 20 times

Online Publication Date: 3 January 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A flat optical device that generates optical vortices with a variety of topological charges is demonstrated. This device spatially modulates light beams over a distance much smaller than the wavelength in the direction of propagation by means of an array of V-shaped plasmonic antennas with sub-wavelength separation. Optical vortices are shown to develop after a sub-wavelength propagation distance from the array, a feature that has major potential implications for integrated optics.
Show PACS
42.79.Hp Optical processors, correlators, and modulators
84.40.Ba Antennas: theory, components and accessories

High field-gradient dysprosium tips for magnetic resonance force microscopy

H. J. Mamin, C. T. Rettner, M. H. Sherwood, L. Gao, and D. Rugar

Appl. Phys. Lett. 100, 013102 (2012); http://dx.doi.org/10.1063/1.3673910 (4 pages) | Cited 4 times

Online Publication Date: 3 January 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Magnetic resonance force microscopy (MRFM) is based on measuring the attonewton-scale force between nuclear or electronic spins and a magnetic tip. The force is directly proportional to the magnetic field gradient generated by the tip, making a high moment nanoscale magnet desirable. Dysprosium, with a bulk magnetization 70% higher than iron, is a suitable candidate for such a tip. We have performed MRFM to quantitatively characterize two Dy nanomagnets. We find that magnetic field gradients as high as 6 MT/m (60 G/nm) can be generated, a 40% enhancement compared to our previous FeCo tips.
Show PACS
75.75.-c Magnetic properties of nanostructures
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
75.30.Cr Saturation moments and magnetic susceptibilities

Observation of nonlinear absorption and visible photoluminescence emission in chemically synthesized Cu2+ doped ZnS nanoparticles

A. K. Kole, P. Kumbhakar, and U. Chatterjee

Appl. Phys. Lett. 100, 013103 (2012); http://dx.doi.org/10.1063/1.3674307 (3 pages) | Cited 3 times

Online Publication Date: 3 January 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Nonlinear optical properties of chemically synthesized ZnS and Cu2+ doped ZnS nanoparticles of average sizes ∼2.5 nm are reported by using open aperture z-scan technique with the Nd:YAG laser second harmonic radiation at 532 nm. Tunable photoluminescence emissions in the visible region due to the increase in concentration of Cu2+ doping in ZnS are observed at room temperature. By analyzing the experimental z-scan data, it is found that three photon absorptions (3PA) are taking place in all the samples. The extracted values of 3PA coefficients of the samples are ∼109 times higher than that of bulk ZnS.
Show PACS
78.67.Bf Nanocrystals, nanoparticles, and nanoclusters
61.46.Df Structure of nanocrystals and nanoparticles ("colloidal" quantum dots but not gate-isolated embedded quantum dots)
81.16.Be Chemical synthesis methods
78.40.Fy Semiconductors
78.55.Et II-VI semiconductors
61.72.uj III-V and II-VI semiconductors

Predicting shape and stability of air–water interface on superhydrophobic surfaces comprised of pores with arbitrary shapes and depths

B. Emami, H. Vahedi Tafreshi, M. Gad-el-Hak, and G. C. Tepper

Appl. Phys. Lett. 100, 013104 (2012); http://dx.doi.org/10.1063/1.3673619 (4 pages) | Cited 6 times

Online Publication Date: 4 January 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
An integro-differential equation for the three dimensional shape of air–water interface on superhydrophobic surfaces comprised of pores with arbitrary shapes and depths is developed and used to predict the static critical pressure under which such surfaces depart from the non-wetting state. Our equation balances the capillary forces with the pressure of the air entrapped in the pores and that of the water over the interface. Stability of shallow and deep circular, elliptical, and polygonal pores is compared with one another and a general conclusion is drawn for designing pore shapes for superhydrophobic surfaces with maximum stability.
Show PACS
68.03.Cd Surface tension and related phenomena
68.08.Bc Wetting
02.60.Lj Ordinary and partial differential equations; boundary value problems

Efficiency enhancement of InGaN multi-quantum-well solar cells via light-harvesting SiO2 nano-honeycombs

P. H. Fu, G. J. Lin, C. H. Ho, C. A. Lin, C. F. Kang, Y. L. Lai, K. Y. Lai, and J. H. He

Appl. Phys. Lett. 100, 013105 (2012); http://dx.doi.org/10.1063/1.3673838 (4 pages) | Cited 3 times

Online Publication Date: 4 January 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Periodic sub-wavelength SiO2 nano-honeycombs are fabricated on GaN-based multiple quantum well solar cells by self-assembly polystyrene nanosphere lithography and reactive ion etching. The nano-honeycombs are found to be effective in suppressing the undesired surface reflections over a wide range of wavelengths. Under the illumination of air mass 1.5G solar simulator, conversion efficiency of the solar cell is enhanced by 24.4%. Simulations based on finite-difference time-domain method indicate that the improved performances result from the enhanced optical absorption in the active region due to the reflection suppression and enhanced forward scattering.
Show PACS
88.40.jm Thin film III-V and II-VI based solar cells
88.40.hj Efficiency and performance of solar cells

Thermal effects on the characteristic Raman spectrum of molybdenum disulfide (MoS2) of varying thicknesses

S. Najmaei, Z. Liu, P. M. Ajayan, and J. Lou

Appl. Phys. Lett. 100, 013106 (2012); http://dx.doi.org/10.1063/1.3673907 (4 pages) | Cited 14 times

Online Publication Date: 4 January 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this letter, thermal effects on the Raman spectra of molybdenum disulfide with thicknesses ranging from bulk to monolayer were evaluated. We quantitatively determined the laser-induced heating effects on the peak position and the line-width of the Raman spectrum. We found considerable thickness-dependent red-shifts as well as line-width changes for both E2g1 and A1g vibrating modes as laser power was increased. Our results enrich the knowledge of phononic behaviors of this material and demonstrate the important effects of the anharmonic terms in the lattice potential energy.
Show PACS
78.30.Hv Other nonmetallic inorganics
81.40.Gh Other heat and thermomechanical treatments
63.20.Ry Anharmonic lattice modes
61.50.Lt Crystal binding; cohesive energy
63.20.D- Phonon states and bands, normal modes, and phonon dispersion
61.82.Ms Insulators
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)

Independent tuning of electron and hole confinement in InAs/GaAs quantum dots through a thin GaAsSbN capping layer

J. M. Ulloa, D. F. Reyes, M. Montes, K. Yamamoto, D. L. Sales, D. González, A. Guzman, and A. Hierro

Appl. Phys. Lett. 100, 013107 (2012); http://dx.doi.org/10.1063/1.3673563 (4 pages) | Cited 4 times

Online Publication Date: 5 January 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The possibility of an independent tuning of the electron and hole confinement in InAs/GaAs quantum dots (QDs) by using a thin GaAsSbN capping layer (CL) is studied. By controlling the Sb and N contents in the quaternary alloy, the band structure of the QDs can be broadly tuned and converted from type-II in the valence band (high Sb contents) to type-I and to type-II in the conduction band (high N contents). Nevertheless, the simultaneous presence of Sb and N is found to induce strain and composition inhomogeneities in the CL and to degrade the photoluminescence of the structure.
Show PACS
73.21.La Quantum dots
78.55.Cr III-V semiconductors
78.67.Hc Quantum dots

Nano-opto-mechanical actuator driven by gradient optical force

H. Cai, K. J. Xu, A. Q. Liu, Q. Fang, M. B. Yu, G. Q. Lo, and D. L. Kwong

Appl. Phys. Lett. 100, 013108 (2012); http://dx.doi.org/10.1063/1.3673854 (3 pages) | Cited 6 times

Online Publication Date: 5 January 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this letter, a nanoscale opto-mechanical actuator driven by gradient optical force is designed and demonstrated. The nanoscale actuator can achieve a maximum displacement of 67 nm with a response time of 94.5 ns. The optical force is estimated as 1.01 pN/μm/mW in C-band operating wavelengths. The device is fabricated on silicon-on-insulator wafer using standard dry etching processes. Compared with traditional microelectromechanical systems actuators driven by electrostatic force, the nanoscale opto-mechanical actuator has the advantages of high resolution of actuation, nanoscale displacement, and fast operating speed. It has potential applications in optical signal processing, chemical, and biological sensing.
Show PACS
85.85.+j Micro- and nano-electromechanical systems (MEMS/NEMS) and devices
85.60.Bt Optoelectronic device characterization, design, and modeling

X-ray luminescence of CdTe quantum dots in LaF3:Ce/CdTe nanocomposites

Marius Hossu, Zhongxin Liu, Mingzhen Yao, Lun Ma, and Wei Chen

Appl. Phys. Lett. 100, 013109 (2012); http://dx.doi.org/10.1063/1.3674313 (3 pages) | Cited 2 times

Online Publication Date: 5 January 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
CdTe quantum dots have intense photoluminescence but exhibit almost no x-ray luminescence. However, intense x-ray luminescence from CdTe quantum dots is observed in LaF3:Ce/CdTe nanocomposites. This enhancement in the x-ray luminescence of CdTe quantum dots is attributed to the energy transfer from LaF3:Ce to CdTe quantum dots in the nanocomposites. The combination of LaF3:Ce nanoparticles and CdTe quantum dots makes LaF3:Ce/CdTe nanocomposites promising scintillators for radiation detection.
Show PACS
78.55.Et II-VI semiconductors
73.21.La Quantum dots
78.67.Hc Quantum dots
78.67.Sc Nanoaggregates; nanocomposites
82.80.Ej X-ray, Mössbauer, and other γ-ray spectroscopic analysis methods

Atomic scale investigation of the abnormal transport properties in bilayer graphene nanoribbon

Yong-Jun Li, Ming-Da Li, Jian-Shuang Liu, Qing-Qing Sun, Peng Zhou, Peng-Fei Wang, Shi-Jin Ding, and David Wei Zhang

Appl. Phys. Lett. 100, 013110 (2012); http://dx.doi.org/10.1063/1.3673324 (3 pages)

Online Publication Date: 5 January 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We investigate the transport properties of bilayer AA-stacking zigzag graphene nanoribbons (bi-zGNRs) and observe abnormal I-V characteristics which are sensitive to the number of carbon chains across the ribbons. Combining the chirality selective rule of Dirac electrons in graphene and the symmetry of eigenstates, we attribute the abnormal current behavior to the chirality mismatch of energy states. The mismatch causes the suppression of transmission pathways between two electrodes which lead to saturated current with increasing bias for certain ribbons.
Show PACS
72.80.Vp Electronic transport in graphene
73.61.Wp Fullerenes and related materials
61.48.Gh Structure of graphene
72.20.Fr Low-field transport and mobility; piezoresistance

Manipulating the size distribution of supported gold nanostructures

A. Sundar, R. A. Hughes, P. Farzinpour, K. D. Gilroy, G. A. Devenyi, J. S. Preston, and S. Neretina

Appl. Phys. Lett. 100, 013111 (2012); http://dx.doi.org/10.1063/1.3675569 (4 pages) | Cited 4 times

Online Publication Date: 6 January 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Gold nanostructures, with a wide size distribution, are confined between a metal foil and the oxide substrate upon which they were formed. When heated the surface energy gradient between the oxide and foil results in a net migration of gold atoms from the nanostructure to the foil. With time, the nanostructures show a size reduction and a narrowed size distribution. The narrowing results from the formation of foil contact points with only the largest nanostructures, a characteristic which leaves small nanostructures intact while consuming larger ones. Also demonstrated is the size reduction of arrayed gold structures to nanoscale dimensions.
Show PACS
61.46.-w Structure of nanoscale materials
81.40.Gh Other heat and thermomechanical treatments
65.40.gp Surface energy

Optical feedback mechanisms in laser induced growth of carbon nanotube forests

M. C. D. Bock, R. Denk, C. T. Wirth, P. Goldberg-Oppenheimer, S. Hofmann, and J. J. Baumberg

Appl. Phys. Lett. 100, 013112 (2012); http://dx.doi.org/10.1063/1.3670328 (3 pages)

Online Publication Date: 6 January 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We study optical feedback mechanisms occurring during growth of multi-walled carbon nanotube forests on transparent substrates. Growth is realised via laser-induced chemical vapour deposition using iron nanoparticle catalysts. In situ Raman and reflection spectroscopy employed clearly distinguish three growth phases. In the initial seed phase, growth of carbon nanostructures increases the laser absorption and this feedback enables growth of radially orientated carbon nanotubes. Understanding the laser interaction with the growing nanostructure holds the key towards controlled growth and opens up new routes to nanostructure and nanodevice design and fabrication.
Show PACS
81.16.Mk Laser-assisted deposition
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
81.07.De Nanotubes
78.67.Ch Nanotubes
61.48.De Structure of carbon nanotubes, boron nanotubes, and other related systems
42.62.-b Laser applications

Quantum transport of Au-S-S-Au nanoscale junctions

Jing-Xin Yu, Xiang-Rong Chen, Stefano Sanvito, and Yan Cheng

Appl. Phys. Lett. 100, 013113 (2012); http://dx.doi.org/10.1063/1.3665614 (4 pages) | Cited 2 times

Online Publication Date: 6 January 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Transport in S2 molecules sandwiched between Au electrodes is investigated with a combination of density functional theory and the non-equilibrium Green’s function method. We consider four different configurations and find that their conductances are related to the details of the bonding geometry. When S2 connects to pyramidal-shaped electrodes at the top site, the transmission is governed by a resonance and is strongly affected by the bias. In contrast, the transport of the remaining three configurations is through several closely spaced broad molecular orbitals, and the transmission coefficient is almost flat around the Fermi level.
Show PACS
85.65.+h Molecular electronic devices
85.35.-p Nanoelectronic devices

Electrical transport in suspended and double gated trilayer graphene

Tymofiy Khodkov, Freddie Withers, David Christopher Hudson, Monica Felicia Craciun, and Saverio Russo

Appl. Phys. Lett. 100, 013114 (2012); http://dx.doi.org/10.1063/1.3675337 (3 pages) | Cited 9 times

Online Publication Date: 6 January 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We present a fabrication process for high quality suspended and double gated trilayer graphene devices. The electrical transport measurements in these transistors reveal a high charge carrier mobility (higher than 20 000 cm2/Vs) and ballistic electric transport on a scale larger than 200 nm. We report a particularly large on/off ratio of the current in ABC-stacked trilayers, up to 250 for an average electric displacement of −0.08 V/nm, compatible with an electric field induced energy gap. The high quality of these devices is also demonstrated by the appearance of quantum Hall plateaus at magnetic fields as low as 500 mT.
Show PACS
85.65.+h Molecular electronic devices
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close