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

23 Dec 2002

Volume 81, Issue 26, pp. 4895-5074

Return to All Sections
back to top
RSS Feeds

Optical microcavities with subnanometer linewidths based on porous silicon

P. J. Reece, G. Lérondel, W. H. Zheng, and M. Gal

Appl. Phys. Lett. 81, 4895 (2002); http://dx.doi.org/10.1063/1.1531226 (3 pages) | Cited 35 times

Online Publication Date: 17 December 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have fabricated a number of high-quality porous silicon optical microcavities operating in the near infrared that exhibit cavity resonances with subnanometer linewidths. This was achieved through the low temperature anodic oxidation of highly doped p-type silicon wafers. We have investigated the optical properties of these microcavities using reflectivity and photoluminescence measurements and compared our results with theoretical predictions. From our analysis, we conclude that, for the low temperature fabrication process, the refractive index difference between adjacent layers of the multilayered structure is maximized while optical losses in the cavity are minimized. Furthermore, by considering the origin of optical losses in these microcavities, we demonstrate that fluctuations in the position of the resonance wavelength and optical absorption play an important role in the realization of high-quality interferometric structures. © 2002 American Institute of Physics.
Show PACS
42.55.Sa Microcavity and microdisk lasers
42.55.Px Semiconductor lasers; laser diodes
42.82.Et Waveguides, couplers, and arrays
78.66.Db Elemental semiconductors and insulators
78.30.Am Elemental semiconductors and insulators
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)

Optical spectroscopy of single InAs/InGaAs quantum dots in a quantum well

S. Kaiser, T. Mensing, L. Worschech, F. Klopf, J. P. Reithmaier, and A. Forchel

Appl. Phys. Lett. 81, 4898 (2002); http://dx.doi.org/10.1063/1.1529315 (3 pages) | Cited 15 times

Online Publication Date: 17 December 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have grown self-assembled InAs quantum dots embedded in the center of an InGaAs quantum well by molecular-beam epitaxy. Using electron-beam lithography and wet etching techniques, small mesas with only a few quantum dots were fabricated. At room temperature, the quantum dots have an emission wavelength of 1.3 μm. By photoluminescence spectroscopy at low temperatures, we observe the emission lines of excitons and biexcitons in single-dot structures. The assignment of exciton and biexciton recombination is based on the characteristic excitation intensity dependence of these states. A biexciton binding energy of about 3.5 meV is obtained for the present dots. © 2002 American Institute of Physics.
Show PACS
78.67.Hc Quantum dots
78.55.Cr III-V semiconductors
78.40.Fy Semiconductors
73.21.La Quantum dots
68.65.Hb Quantum dots (patterned in quantum wells)
71.35.Cc Intrinsic properties of excitons; optical absorption spectra
78.30.Fs III-V and II-VI semiconductors

Comprehensive above-threshold analysis of large-aperture (8–10 μm) antiresonant reflecting optical waveguide diode lasers

J. C. Chang, J. J. Lee, A. Al-Muhanna, L. J. Mawst, and D. Botez

Appl. Phys. Lett. 81, 4901 (2002); http://dx.doi.org/10.1063/1.1531830 (3 pages) | Cited 3 times

Online Publication Date: 17 December 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
An above-threshold analysis of 8–10-μm-core antiresonant reflecting optical waveguide (ARROW) lasers is performed, including the carrier-induced index depression, carrier diffusion, and gain spatial hole burning (GSHB). The study is done as a function of the (transverse) optical-mode confinement factor Γ and the core width. Just as for index-guided devices, it is found that ARROW devices (i.e., index-antiguided devices) are much less immune to multimoding via GSHB the smaller the value of Γ. For the case Γ=3%, the high-order mode of most concern reaches the threshold much earlier than for the case Γ=1%, due both to gain-profile distortion as well as to distortion of the effective-index profile (in the device core) with increasing drive level. Devices of 8.5-μm-wide cores and Γ=1%, are found to stay single-mode to at least 40× threshold, which in turn allows the projection of stable, single-mode operation to 1.2 W output power. In contrast, 10-μm-core devices become multimode at around 10× threshold. Preliminary experimental results from 10-μm-wide core ARROW lasers, with Γ=1.5%, are stable, single-mode operation to 300 mW at 10× threshold, in good agreement with the presented study. © 2002 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
42.50.Hz Strong-field excitation of optical transitions in quantum systems; multiphoton processes; dynamic Stark shift
42.50.Md Optical transient phenomena: quantum beats, photon echo, free-induction decay, dephasings and revivals, optical nutation, and self-induced transparency
42.60.By Design of specific laser systems
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)

Experimental investigation of the effect of wetting-layer states on the gain–current characteristic of quantum-dot lasers

D. R. Matthews, H. D. Summers, P. M. Smowton, and M. Hopkinson

Appl. Phys. Lett. 81, 4904 (2002); http://dx.doi.org/10.1063/1.1532549 (3 pages) | Cited 73 times

Online Publication Date: 17 December 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Using experimental measurements of the gain–current characteristic as a function of temperature in InGaAs quantum-dot lasers, we demonstrate that it is the population of wetting-layer states that leads to a saturation of the population inversion in dot states and hence to the saturation of gain in a quantum-dot laser. At 300 K, the maximum modal gain for a three-layer structure is reduced from 53 to 14 cm−1. © 2002 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
73.21.La Quantum dots

Optimal rubbing angle for reflective in-plane-switching liquid crystal displays

Yubao Sun, Zhidong Zhang, Hongmei Ma, Xinyu Zhu, and Shin-Tson Wu

Appl. Phys. Lett. 81, 4907 (2002); http://dx.doi.org/10.1063/1.1532534 (3 pages) | Cited 19 times

Online Publication Date: 17 December 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Rubbing angle effects on the response time and optical threshold voltage of the reflective in-plane-switching homogeneous liquid crystal displays were analyzed. As the rubbing angle increases, the rise time decreases except that its operating voltage also increases. The optimal rubbing angle is around 30°–40°. © 2002 American Institute of Physics.
Show PACS
42.79.Kr Display devices, liquid-crystal devices

Milliwatt power deep ultraviolet light-emitting diodes over sapphire with emission at 278 nm

J. P. Zhang, A. Chitnis, V. Adivarahan, S. Wu, V. Mandavilli, R. Pachipulusu, M. Shatalov, G. Simin, J. W. Yang, and M. Asif Khan

Appl. Phys. Lett. 81, 4910 (2002); http://dx.doi.org/10.1063/1.1531835 (3 pages) | Cited 73 times

Online Publication Date: 17 December 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report on AlGaN multiple-quantum-well (MQW)-based deep ultraviolet light-emitting diodes over sapphire with peak emission at 278 nm. A new buffer layer growth process was used to reduce the number of defects and hence the nonradiative recombination. The improved material quality and carrier confinement resulted in pulsed powers as high as 3 mW at 278 nm and a significantly reduced deep-level-assisted long-wavelength emission. © 2002 American Institute of Physics.
Show PACS
85.60.Jb Light-emitting devices
85.35.Be Quantum well devices (quantum dots, quantum wires, etc.)

Pure red electroluminescence from a host material of binuclear gallium complex

Juan Qiao, Yong Qiu, Liduo Wang, Lian Duan, Yang Li, and Deqiang Zhang

Appl. Phys. Lett. 81, 4913 (2002); http://dx.doi.org/10.1063/1.1532756 (3 pages) | Cited 30 times

Online Publication Date: 17 December 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
By using a binuclear gallium complex, bis(salicylidene-o-aminophenolato)-bis(8quinolinoato)-bisgallium(III)[Ga2(saph)2q2], as the host material, organic light emitting diodes (OLEDs) with pure red emission were developed, which used a red fluorescent dye of 4-(dicyanomethylene)-2-t-butyle-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)4H-pyran (DCJTB). Ga2(saph)2q2 proves to be of much better film-forming ability and a smaller energy gap than tris(8-quinolinolato)aluminum (Alq3). And the doped device with a configuration of indium tinoxide/N,N′-bis-(1-naphthl)-diphenyl-1,1′-biphenyl-4,4′-diamine/Ga2(saph)2q2: DCJTB (2wt %)/Ga2(saph)2q2/Mg:Ag, exhibited a turn-on voltage as low as 2.2 V, and a pure red emission with Commission Internationale de l’Eclairage (CIE 1931) coordinates of (0.67, 0.33). The improved energy transfer gave a high current efficiency of 2.04 cd/A at 20 mA/cm2, which is about two times higher than that of the doped Alq3 device. This letter indicates that developing host materials is a promising way to achieve excellent red emission OLEDs. © 2002 American Institute of Physics.
Show PACS
78.60.Fi Electroluminescence
85.60.Jb Light-emitting devices
42.70.Jk Polymers and organics

Post-growth p-type doping enhancement for ZnSe-based lasers using a Li3N interlayer

Oliver Schulz, Matthias Strassburg, Thorsten Rissom, Udo W. Pohl, Dieter Bimberg, Matthias Klude, and Detlef Hommel

Appl. Phys. Lett. 81, 4916 (2002); http://dx.doi.org/10.1063/1.1532544 (3 pages) | Cited 5 times

Online Publication Date: 17 December 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A method to increase decisively the p-type doping level in ZnSe-based laser diodes is described. Upon Li3N indiffusion, the formation of a stable acceptor complex is observed. Free hole concentrations of 8×1018 cm−3 are obtained. This value is at least one order of magnitude larger than typical p-type doping levels achieved by molecular-beam epitaxy of ZnSe. In addition, no compensation effects occur, as usually observed for p-type doping using either Li or N. ZnSe-based lasers processed by applying this post-growth p-doping enhancement technology show significantly improved properties. © 2002 American Institute of Physics.
Show PACS
42.55.Px Semiconductor lasers; laser diodes
61.72.uj III-V and II-VI semiconductors
68.35.Fx Diffusion; interface formation

Scattering rings in optically anisotropic porous silicon

C. J. Oton, Z. Gaburro, M. Ghulinyan, L. Pancheri, P. Bettotti, L. Dal Negro, and L. Pavesi

Appl. Phys. Lett. 81, 4919 (2002); http://dx.doi.org/10.1063/1.1531834 (3 pages) | Cited 14 times

Online Publication Date: 17 December 2002

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report the observation of strongly anisotropic scattering of laser light at oblique incidence on a (100)-oriented porous silicon layer. The scattered light forms cones tangent to the incident and reflected beams. The conical pattern is caused by scattering on the vertical walls of pores, which are straight along the layer thickness. The light cone defines structured light rings onto a screen normal to the cone axis. We explain the various structures by optical anisotropy of porous silicon. For the sample under analysis, we directly measure from the ring patterns a value of Δn/nord = 8% of positive birefringence. © 2002 American Institute of Physics.
Show PACS
78.35.+c Brillouin and Rayleigh scattering; other light scattering
78.20.Fm Birefringence
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close