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J. P. Harbison

Other affiliations: Bell Labs
Bio: J. P. Harbison is an academic researcher from Telcordia Technologies. The author has contributed to research in topics: Molecular beam epitaxy & Quantum well. The author has an hindex of 55, co-authored 292 publications receiving 11668 citations. Previous affiliations of J. P. Harbison include Bell Labs.


Papers
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Journal ArticleDOI
TL;DR: In this paper, conditions for the selective lift-off of large area epitaxial AlxGa1−xAs films from the substrate wafers on which they were grown were discovered.
Abstract: We have discovered conditions for the selective lift‐off of large area epitaxial AlxGa1−xAs films from the substrate wafers on which they were grown. A 500‐A‐thick AlAs release layer is selectivity etched away, leaving behind a high‐quality epilayer and a reusable GaAs substrate. We have measured a selectivity of ≳107 between the release layer and Al0.4Ga0.6As. This process relies upon the creation of a favorable geometry for the outdiffusion of dissolved H2 gas from the etching zone.

895 citations

Journal ArticleDOI
Jack L. Jewell1, J. P. Harbison, Axel Scherer2, Yong-Hee Lee, L. T. Florez2 
TL;DR: In this paper, the authors have designed, fabricated, and tested vertical-cavity surface-emitting laser (VCSEL) with diameters ranging from 0.5 mu m to>50 mu m.
Abstract: The authors have designed, fabricated, and tested vertical-cavity surface-emitting lasers (VCSEL) with diameters ranging from 0.5 mu m to>50 mu m. Design issues, molecular beam epitaxial growth, fabrication, and lasing characteristics are discussed. The topics considered in fabrication of VCSELs are microlaser geometries; ion implementation and masks; ion beam etching packaging and arrays, and ultrasmall devices. >

544 citations

Journal ArticleDOI
TL;DR: In this paper, a multilayer AlxGa1−xAs epitaxial films are separated from their growth substrates by undercutting an AlAs release layer in HF acid (selectivity ≳108 for x ≥ 0.4).
Abstract: Epitaxial liftoff is an alternative to lattice‐mismatched heteroepitaxial growth. Multilayer AlxGa1−xAs epitaxial films are separated from their growth substrates by undercutting an AlAs release layer in HF acid (selectivity ≳108 for x≤0.4). The resulting AlxGa1−xAs films tend to bond by natural intermolecular surface forces to any smooth substrate (Van der Waals bonding). We have demonstrated GaAs thin‐film bonding by surface tension forces onto Si, glass, sapphire, LiNbO3, InP, and diamond substrates, as well as self‐bonding onto GaAs substrates. In transmission electron microscopy the substrate and thin‐film atomic lattices can be simultaneously imaged, showing only a thin (20–100 A) amorphous layer in between.

435 citations

Journal ArticleDOI
TL;DR: In this article, an accuracy analysis of several possible reflectance-difference (RD) configurations that are compatible with standard molecular-beam epitaxy (MBE) growth chambers is performed, and an optical-bridge system that can determine relative changes in RD signals as small as 5×10−5 under standard growth conditions.
Abstract: We perform an accuracy analysis of several possible reflectance–difference (RD) configurations that are compatible with standard molecular‐beam epitaxy (MBE) growth chambers, and describe in detail an optical‐bridge system that can determine relative changes in RD signals as small as 5×10−5 under standard growth conditions. Using this system, we determine the RD response of GaAs for changes in surface conditions at different wavelengths and correlate these to simultaneously measured reflection high‐energy electron diffraction (RHEED) intensities. Maximum anisotropies are found at 2.0–2.5 and 3.5 eV for Ga on GaAs and Al on AlAs, respectively, providing a way of spectrally distinguishing Ga–Ga and Al–Al dimers for surface‐chemical investigations, and suggesting that these photon energies are also optimal for modifying growth by light. At photon energies well removed from these anisotropy maxima, RD signals follow changes in surface structure, as RHEED. Our RD‐RHEED correlations provide insight concerning c...

429 citations

Journal ArticleDOI
TL;DR: In this paper, the dynamic, polarization, and transverse mode characteristics of InGaAs-GaAs quantum well vertical cavity surface emitting lasers (VCSELs) emitting at 0.98 mu m are investigated.
Abstract: The dynamic, polarization, and transverse mode characteristics of strained InGaAs-GaAs quantum well vertical cavity surface emitting lasers (VCSELs) emitting at 0.98 mu m are investigated. The dynamic behavior of VCSELs with high and low operating voltages and series resistances is compared. A large wavelength chirp in the lasing spectrum was observed for the lasers with high voltage/resistance, even under low-duty-cycle pulse operation. This is thought to be due to resistive heating close to the laser junction. It is observed that the transverse mode structure of VCSELs and their dependence on laser dimensions and drive current are highly analogous to those of edge emitting lasers, whereas the polarization characteristics of the two types of lasers are significantly different. >

406 citations


Cited by
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Journal ArticleDOI
TL;DR: If a three-dimensionally periodic dielectric structure has an electromagnetic band gap which overlaps the electronic band edge, then spontaneous emission can be rigorously forbidden.
Abstract: It has been recognized for some time that the spontaneous emission by atoms is not necessarily a fixed and immutable property of the coupling between matter and space, but that it can be controlled by modification of the properties of the radiation field. This is equally true in the solid state, where spontaneous emission plays a fundamental role in limiting the performance of semiconductor lasers, heterojunction bipolar transistors, and solar cells. If a three-dimensionally periodic dielectric structure has an electromagnetic band gap which overlaps the electronic band edge, then spontaneous emission can be rigorously forbidden.

12,787 citations

Journal ArticleDOI
TL;DR: The interest in nanoscale materials stems from the fact that new properties are acquired at this length scale and, equally important, that these properties are equally important.
Abstract: The interest in nanoscale materials stems from the fact that new properties are acquired at this length scale and, equally important, that these properties * To whom correspondence should be addressed. Phone, 404-8940292; fax, 404-894-0294; e-mail, mostafa.el-sayed@ chemistry.gatech.edu. † Case Western Reserve UniversitysMillis 2258. ‡ Phone, 216-368-5918; fax, 216-368-3006; e-mail, burda@case.edu. § Georgia Institute of Technology. 1025 Chem. Rev. 2005, 105, 1025−1102

6,852 citations

Journal ArticleDOI
TL;DR: The reflectance and the phase change on reflection from semiconductor-metal interfaces (including the case of metallic multilayers) can be accurately described by use of the proposed models for the optical functions of metallic films and the matrix method for multilayer calculations.
Abstract: We present models for the optical functions of 11 metals used as mirrors and contacts in optoelectronic and optical devices: noble metals (Ag, Au, Cu), aluminum, beryllium, and transition metals (Cr, Ni, Pd, Pt, Ti, W). We used two simple phenomenological models, the Lorentz-Drude (LD) and the Brendel-Bormann (BB), to interpret both the free-electron and the interband parts of the dielectric response of metals in a wide spectral range from 0.1 to 6 eV. Our results show that the BB model was needed to describe appropriately the interband absorption in noble metals, while for Al, Be, and the transition metals both models exhibit good agreement with the experimental data. A comparison with measurements on surface normal structures confirmed that the reflectance and the phase change on reflection from semiconductor-metal interfaces (including the case of metallic multilayers) can be accurately described by use of the proposed models for the optical functions of metallic films and the matrix method for multilayer calculations.

3,629 citations

Journal ArticleDOI
TL;DR: In this article, three QD solar cell configurations are described: (1) photoelectrodes comprising QD arrays, (2) QD-sensitized nanocrystalline TiO 2, and (3) QDs dispersed in a blend of electron- and hole-conducting polymers.
Abstract: Quantum dot (QD) solar cells have the potential to increase the maximum attainable thermodynamic conversion efficiency of solar photon conversion up to about 66% by utilizing hot photogenerated carriers to produce higher photovoltages or higher photocurrents. The former effect is based on miniband transport and collection of hot carriers in QD array photoelectrodes before they relax to the band edges through phonon emission. The latter effect is based on utilizing hot carriers in QD solar cells to generate and collect additional electron–hole pairs through enhanced impact ionization processes. Three QD solar cell configurations are described: (1) photoelectrodes comprising QD arrays, (2) QD-sensitized nanocrystalline TiO 2 , and (3) QDs dispersed in a blend of electron- and hole-conducting polymers. These high-efficiency configurations require slow hot carrier cooling times, and we discuss initial results on slowed hot electron cooling in InP QDs.

2,405 citations

Journal ArticleDOI
11 Jun 1999-Science
TL;DR: A laser cavity formed from a single defect in a two-dimensional photonic crystal is demonstrated and pulsed lasing action has been observed at a wavelength of 1.5 micrometers from optically pumped devices with a substrate temperature of 143 kelvin.
Abstract: A laser cavity formed from a single defect in a two-dimensional photonic crystal is demonstrated. The optical microcavity consists of a half wavelength–thick waveguide for vertical confinement and a two-dimensional photonic crystal mirror for lateral localization. A defect in the photonic crystal is introduced to trap photons inside a volume of 2.5 cubic half-wavelengths, approximately 0.03 cubic micrometers. The laser is fabricated in the indium gallium arsenic phosphide material system, and optical gain is provided by strained quantum wells designed for a peak emission wavelength of 1.55 micrometers at room temperature. Pulsed lasing action has been observed at a wavelength of 1.5 micrometers from optically pumped devices with a substrate temperature of 143 kelvin.

2,310 citations