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

9 Apr 2001

Volume 78, Issue 15, pp. 2095-2255

Return to All Sections
back to top
RSS Feeds

Temperature profile of GaInAs/AlInAs/InP quantum cascade-laser facets measured by microprobe photoluminescence

Vincenzo Spagnolo, Mariano Troccoli, Gaetano Scamarcio, Claire Gmachl, Federico Capasso, Alessandro Tredicucci, A. Michael Sergent, Albert L. Hutchinson, Deborah L. Sivco, and Alfred Y. Cho

Appl. Phys. Lett. 78, 2095 (2001); http://dx.doi.org/10.1063/1.1359146 (3 pages) | Cited 36 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The local temperature of quantum-cascade lasers operating in continuous wave mode is reported. This information is extracted from the thermal shift of the band-to-band photoluminescence peaks in the AlInAs and InP cladding layers of quantum-cascade laser facets using a high-resolution microprobe setup. Interpolation by means of a two-dimensional heat diffusion model allows to obtain the temperature profile and the thermal conductivity in the waveguide core. Comparison between substrate and epilayer-side mounted lasers shows the superior thermal dissipation capability of the latter, and explains their better performance with respect to threshold current and maximum operating temperature. © 2001 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
78.55.Cr III-V semiconductors
78.67.De Quantum wells
68.65.Fg Quantum wells
66.70.-f Nonelectronic thermal conduction and heat-pulse propagation in solids; thermal waves

Dispersion of the ordinary refractive-index change in a proton-exchanged LiNbO3 waveguide

R. Ramponi, M. Marangoni, and R. Osellame

Appl. Phys. Lett. 78, 2098 (2001); http://dx.doi.org/10.1063/1.1359136 (3 pages) | Cited 10 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The wavelength dependence of the ordinary refractive-index change of a proton exchanged LiNbO3 waveguide is determined by applying a recently proposed method based on radiation modes. A peculiar behavior is observed since the absolute value of the ordinary index change increases with the wavelength, while the extraordinary one decreases. The Sellmeier curves for the dispersion of both the index changes are provided in the wavelength range from λ = 0.514 μm to λ = 1.554 μm. © 2001 American Institute of Physics.
Show PACS
42.79.Gn Optical waveguides and couplers
42.65.Wi Nonlinear waveguides
42.86.+b Optical workshop techniques

Leveraging deep photonic band gaps in photonic crystal impurity bands

Sheng Lan, Satoshi Nishikawa, and Osamu Wada

Appl. Phys. Lett. 78, 2101 (2001); http://dx.doi.org/10.1063/1.1362328 (3 pages) | Cited 34 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Photonic band gaps can be generated in the impurity bands of photonic crystals formed by periodically placed defects. Even slight periodic modulation of the properties of these defects can open up very deep band gaps in the impurity bands. This phenomenon originates from the concentration of electromagnetic field at the defect regions, making electromagnetic wave extremely sensitive to the small changes of the defects. A dynamical photonic band gap in the impurity band created by a control light, provides a mechanism for constructing high-efficiency optical switches. © 2001 American Institute of Physics.
Show PACS
42.70.Qs Photonic bandgap materials
77.22.Ch Permittivity (dielectric function)
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)

Origin of abnormal temperature dependence of electroluminescence from Er/O-doped Si diodes

G. V. Hansson, W.-X. Ni, C.-X. Du, A. Elfving, and F. Duteil

Appl. Phys. Lett. 78, 2104 (2001); http://dx.doi.org/10.1063/1.1359781 (3 pages) | Cited 12 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The temperature dependencies of the current–voltage characteristics and the electroluminescence (EL) intensity of molecular beam epitaxy grown Er/O-doped Si light emitting diodes at reverse bias have been studied. To minimize the scattering of electrons injected from the p-doped Si1−xGex electron emitters, an intrinsic Si layer was used in the depletion region. For many diodes, there is a temperature range where the EL intensity increases with temperature. Data are reported for a structure that shows increasing intensity up to 100 °C. This is attributed to an increasing fraction of the pumping current being due to phonon-assisted tunneling, which gives a higher saturation intensity, compared to ionization-dominated breakdown at lower temperatures. © 2001 American Institute of Physics.
Show PACS
78.66.Db Elemental semiconductors and insulators
78.60.Fi Electroluminescence
85.60.Jb Light-emitting devices

High-performance InAs/GaSb superlattice photodiodes for the very long wavelength infrared range

H. Mohseni, M. Razeghi, G. J. Brown, and Y. S. Park

Appl. Phys. Lett. 78, 2107 (2001); http://dx.doi.org/10.1063/1.1362179 (3 pages) | Cited 30 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on the demonstration of high-performance p-i-n photodiodes based on type-II InAs/GaSb superlattices with 50% cut-off wavelength λc = 16 μm operating at 80 K. Material is grown by molecular beam epitaxy on GaSb substrates with excellent crystal quality as evidenced by x-ray diffraction and atomic force microscopy. The processed devices show a current responsivity of 3.5 A/W at 80 K leading to a detectivity of ∼ 1.51×1010 cmHz1/2/W. The quantum efficiency of these devices is about 35% which is comparable to HgCdTe detectors with a similar active layer thickness. © 2001 American Institute of Physics.
Show PACS
07.57.Kp Bolometers; infrared, submillimeter wave, microwave, and radiowave receivers and detectors
85.60.Gz Photodetectors (including infrared and CCD detectors)
85.60.Dw Photodiodes; phototransistors; photoresistors
68.65.Cd Superlattices
78.67.-n Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy

Low-loss polymeric optical waveguides using electron-beam direct writing

W. H. Wong, J. Zhou, and E. Y. B. Pun

Appl. Phys. Lett. 78, 2110 (2001); http://dx.doi.org/10.1063/1.1361287 (3 pages) | Cited 28 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Low-loss optical waveguides based on a negative tone epoxy Novolak resin polymer have been fabricated using electron-beam direct writing. This polymer has a high refractive index, high sensitivity, large hardness, and Tg>200 °C. For single-mode channel waveguides with upper claddings, the propagation losses measured were 0.22 and 0.48 dB/cm at 1330 and 1550 nm, respectively. For waveguides without upper claddings, the losses were 0.5 dB/cm at both wavelengths. The stability of these waveguides was also investigated, and no significant change was observed after 200 h at 90 °C and 95% relative humidity. © 2001 American Institute of Physics.
Show PACS
42.70.Jk Polymers and organics
42.79.Gn Optical waveguides and couplers
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
42.86.+b Optical workshop techniques

Large improvement of pumping rate in the He–CuCl–NiBr2 laser system

H. Saito, Y. Shiraiwa, T. Ishikawa, K. Uno, and K. Fujii

Appl. Phys. Lett. 78, 2113 (2001); http://dx.doi.org/10.1063/1.1358849 (3 pages) | Cited 2 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A Ni atom is employed as the energy donor to a Cu upper laser level. After the energy transfer is done by collision between Ni and Cu atoms, the population of the Cu upper laser level is enhanced via a cascading decay resulting in a four-level excitation loop. The peak value of the lasing pulse was increased by a rate of 400%, whereas the pulse width was not changed. The near-infrared spectra, λ = 809.3 and 793.3 nm, emitted via this cascading decay method, were also observed and the intensity properties agreed with that of the lasing lines. © 2001 American Institute of Physics.
Show PACS
42.55.Lt Gas lasers including excimer and metal-vapor lasers
32.80.Xx Level crossing and optical pumping
32.50.+d Fluorescence, phosphorescence (including quenching)

Correlation between dark spot growth and pinhole size in organic light-emitting diodes

Shuang Fang Lim, Lin Ke, Wei Wang, and Soo Jin Chua

Appl. Phys. Lett. 78, 2116 (2001); http://dx.doi.org/10.1063/1.1364658 (3 pages) | Cited 29 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Our in situ experimental observations of dark spot growth in organic light-emitting diodes using optical microscopy show a linear rate of growth for the area of all the dark spots. We used uniformly sized silica micro particles to intentionally create size-controllable pinholes on the cathode protective layer. Subsequently, we observed initial formation of dark spots as a result of these pinholes and then monitored their growth. Due to usage of particles of various diameters, we were able to linearly correlate the growth rate with pinhole size. This allows us to estimate the original pinhole sizes that gave rise to the dark spots, which we believe were initiated by “dust” particles. Our studies verify that dark spot formation is due to pinholes on the protective layer that creates pathways for water or oxygen permeation, and that dark spot growth is dependent on the pinhole sizes. © 2001 American Institute of Physics.
Show PACS
85.60.Jb Light-emitting devices

Reduction in surface recombination of GaInAsP microcolumns by CH4 plasma irradiation

Hiroyuki Ichikawa, Kyoji Inoshita, and Toshihiko Baba

Appl. Phys. Lett. 78, 2119 (2001); http://dx.doi.org/10.1063/1.1364506 (3 pages) | Cited 20 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We evaluated the surface recombination velocity vs of 1.55 μm GaInAsP microcolumns through the measurement of carrier lifetime using the phase-resolved spectroscopy. We investigated various surface treatments and confirmed that vs was reduced to nearly half of that for as-etched microcolumns by CH4 electron cyclotron resonance plasma irradiation. This result was ensured by the two- to fivefold increase in photoluminescence intensity. The secondary ion mass spectroscopy analysis suggested that the reduction in vs was attributable to the deposition of a polymer, the hydrogenated hard carbon, etc., and/or a carbon deep level formed near the surface. © 2001 American Institute of Physics.
Show PACS
73.25.+i Surface conductivity and carrier phenomena
78.55.Cr III-V semiconductors
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping
52.77.Bn Etching and cleaning
81.65.Cf Surface cleaning, etching, patterning
82.80.Ms Mass spectrometry (including SIMS, multiphoton ionization and resonance ionization mass spectrometry, MALDI)
73.63.-b Electronic transport in nanoscale materials and structures

Near-infrared electroluminescence of polymer light-emitting diodes doped with a lissamine-sensitized Nd3+ complex

L. H. Slooff, A. Polman, F. Cacialli, R. H. Friend, G. A. Hebbink, F. C. J. M. van Veggel, and D. N. Reinhoudt

Appl. Phys. Lett. 78, 2122 (2001); http://dx.doi.org/10.1063/1.1359782 (3 pages) | Cited 69 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report 890 nm luminescence from a neodymium-doped polymer light-emitting diode. The active layer is a blend of poly(dioctylfluorene-co-benzothiadiazole), F8BT, and a lissamine-functionalized terphenyl-based neodymium complex. We detect electroluminescence from both the lissamine (580 nm) and the Nd3+ complex (890 nm). By comparison with lissamine-free devices we show that the lissamine is crucial to infrared emission. The neodymium/lissamine luminescence intensity ratio is higher under electrical excitation than under optical excitation, showing that more triplets reach Nd3+ under electrical excitation. High turn-on voltages provide a clear indication for charge trapping onto the lissamine, and we consider direct triplet formation on the lissamine to be competing efficiently with respect to slower Dexter-type triplet transfer from the F8BT to the lissamine. © 2001 American Institute of Physics.
Show PACS
85.60.Jb Light-emitting devices
78.60.Fi Electroluminescence
78.66.Qn Polymers; organic compounds

Photosensitivity in phosphate glass doped with Ag+ upon exposure to near-ultraviolet femtosecond laser pulses

Yuichi Watanabe, Gaku Namikawa, Teppei Onuki, Keishi Nishio, and Toshio Tsuchiya

Appl. Phys. Lett. 78, 2125 (2001); http://dx.doi.org/10.1063/1.1361284 (3 pages) | Cited 24 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on a photosensitivity in soda-alumino-phosphate glass doped with silver ions Ag+ upon exposure to near-ultraviolet femtosecond laser pulses. The photosensitivity, i.e., formation of color centers such as Ag0 and Ag2+ in the glass is found to be associated with intensity-dependent nonlinear optical process induced by extremely high irradiance up to ∼ TW/cm2 of the femtosecond pulses. We demonstrate a bright orange fluorescence from the induced color centers inside the glass, that should be applicable to a functional optical device. © 2001 American Institute of Physics.
Show PACS
42.70.Gi Light-sensitive materials
42.70.Ce Glasses, quartz
61.43.Fs Glasses
78.55.Hx Other solid inorganic materials
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
61.82.Ms Insulators
42.70.Nq Other nonlinear optical materials; photorefractive and semiconductor materials
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close