We present a comprehensive, up-to-date compilation of band parameters for the technologically important III–V zinc blende and wurtzite compound semiconductors: GaAs, GaSb, GaP, GaN, AlAs, AlSb, AlP, AlN, InAs, InSb, InP, and InN, along with their ternary and quaternary alloys. Based on a review of the existing literature, complete and consistent parameter sets are given for all materials. Emphasizing the quantities required for band structure calculations, we tabulate the direct and indirect energy gaps, spin-orbit, and crystal-field splittings, alloy bowing parameters, effective masses for electrons, heavy, light, and split-off holes, Luttinger parameters, interband momentum matrix elements, and deformation potentials, including temperature and alloy-composition dependences where available. Heterostructure band offsets are also given, on an absolute scale that allows any material to be aligned relative to any other.

Band parameters for III–V compound semiconductors and their alloys

A new type of semiconductor laser is studied, in which injected carriers in the active region are quantum mechanically confined in two or three dimensions (2D or 3D). Effects of such confinements on the lasing characteristics are analyzed. Most important, the threshold current of such laser is predicted to be far less temperature sensitive than that of conventional lasers, reflecting the reduced dimensionality of electronic state. In the case of 3D‐QW laser, the temperature dependence is virtually eliminated. An experiment on 2D quantum well lasers is performed by placing a conventional laser in a strong magnetic field (30 T) and has demonstrated the predicted increase of T0 value from 144 to 313 °C.

Multidimensional quantum well laser and temperature dependence of its threshold current

Electron and ambipolar transport in organic field-effect transistors.

Status and future outlook of III-V compound semiconductor visible-spectrum light-emitting diodes (LEDs) are presented. Light extraction techniques are reviewed and extraction efficiencies are quantified in the 60%+ (AlGaInP) and ~80% (InGaN) regimes for state-of-the-art devices. The phosphor-based white LED concept is reviewed and recent performance discussed, showing that high-power white LEDs now approach the 100-lm/W regime. Devices employing multiple phosphors for "warm" white color temperatures (~3000-4000 K) and high color rendering (CRI>80), which provide properties critical for many illumination applications, are discussed. Recent developments in chip design, packaging, and high current performance lead to very high luminance devices (~50 Mcd/m2 white at 1 A forward current in 1times1 mm2 chip) that are suitable for application to automotive forward lighting. A prognosis for future LED performance levels is considered given further improvements in internal quantum efficiency, which to date lag achievements in light extraction efficiency for InGaN LEDs

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Status and Future of High-Power Light-Emitting Diodes for Solid-State Lighting

We report experiments and theory on the effects of electric fields on the optical absorption near the band edge in GaAs/AlGaAs quantum-well structures. We find distinct physical effects for fields parallel and perpendicular to the quantum-well layers. In both cases, we observe large changes in the absorption near the exciton peaks. In the parallel-field case, the excitons broaden with field, disappearing at fields \ensuremath{\sim}${10}^{4}$ V/cm; this behavior is in qualitative agreement with previous theory and in order-of-magnitude agreement with direct theoretical calculations of field ionization rates reported in this paper. This behavior is also qualitatively similar to that seen with three-dimensional semiconductors. For the perpendicular-field case, we see shifts of the exciton peaks to lower energies by up to 2.5 times the zero-field binding energy with the excitons remaining resolved at up to \ensuremath{\sim}${10}^{5}$ V/cm: This behavior is qualitatively different from that of bulk semiconductors and is explained through a mechanism previously briefly described by us [D. A. B. Miller et al., Phys. Rev. Lett. 53, 2173 (1984)] called the quantum-confined Stark effect. In this mechanism the quantum confinement of carriers inhibits the exciton field ionization. To support this mechanism we present detailed calculations of the shift of exciton peaks including (i) exact solutions for single particles in infinite wells, (ii) tunneling resonance calculations for finite wells, and (iii) variational calculations of exciton binding energy in a field. We also calculate the tunneling lifetimes of particles in the wells to check the inhibition of field ionization. The calculations are performed using both the 85:15 split of band-gap discontinuity between conduction and valence bands and the recently proposed 57:43 split. Although the detailed calculations differ in the two cases, the overall shift of the exciton peaks is not very sensitive to split ratio. We find excellent agreement with experiment with no fitted parameters.

Electric field dependence of optical absorption near the band gap of quantum-well structures.

Photosensitive Impurity-Assisted Tunneling in Au-Ge-Doped Ga 1-x Al x As p-n Diodes

Data are presented showing that it is possible to operate lightly doped GaAs as a laser at energies exceeding 1.500 eV at 77°K (Eg=1.513 eV), to obtain essentially monoenergetic operation well above threshold and to avoid the mode jumping effects common to optically pumped lasers. This has been accomplished by volume exciting the center n region (selective absorption) of a low‐loss n+/n/n+ epitaxial wafer under conditions of limited absorption which in turn allows stabilization of the carrier concentration and the photon energy of the recombination radiation.

Near‐Bandgap, Narrow‐Spectrum, Low‐Loss, Volume‐Excited GaAs Laser (77°K) with Time‐Uniform Output

AlxGa1−xAs–GaAs–InyGa1−yAs quantum well heterostructure lasers with thin sharply defined cavities that operate longitudinally or vertically are demonstrated Longitudinally, the cavity is defined by cleaving (edge emission) while vertical definition is provided by a lower AlxOy/GaAs distributed Bragg reflector (DBR) and an upper SiO2/Si DBR that form a resonant structure A reverse-biased tunnel contact junction provides lateral electron current to support hole injection through a native-oxide-defined aperture This ultrathin cavity configuration produces low threshold high efficiency (η∼91%, L=140 μm) edge emission (longitudinal operation) in the case of long lasers (L≳90 μm), and vertical emission for shorter lasers (L≲65 μm) The transition from longitudinal to vertical laser operation as a function of cavity length, L, is demonstrated

Transition from edge to vertical cavity operation of tunnel contact algaas-gaas-ingaas quantum well heterostructure lasers

We investigate a tunneling injection InP quantum-dot (QD) laser theoretically and experimentally. The device consists of a single compressively strained InP QD layer coupled closely to two tensile strained InGaP quantum wells (QWs). While most tensile strained QW lasers in this wavelength (red) range lase in the transverse-magnetic (TM) polarization, our QD laser lases in the transverse-electric (TE) polarization from the first excited state of the compressively strained QDs, which is coupled to the ground state of the tensile-strained InGaP QWs. When we measure TE and TM modal gain spectra, a typical QW gain evolution behavior is observed at low injection currents, which can be theoretically explained by the quasi-equilibrium of carrier distribution. When the injection current is increased near threshold, a TE gain narrowing and a simultaneous TM gain pinning are observed in the measured modal gain spectra, which cannot be explained via the quasi-equilibrium model. We propose a polarization-dependent photon-mediated carrier re-distribution in the QD-coupled-QW structure to explain this TE and TM gain evolution behavior. When the injection current is just below threshold, the strong carrier depletion via stimulated emission due to coupling between the InP QD and InGaP QW states plays an important role in carrier re-distribution, which depends on the optical transition energy and polarization. This polarization-dependent photon-mediated carrier re-distribution explains the TE gain narrowing and TM gain pinning behavior. To quantitatively demonstrate the photon-mediated carrier re-distribution near the threshold current, a set of coupled rate equations are solved taking into account the polarization-dependent stimulated emission processes. The calculated polarization power ratio based on the coupled rate equations explains the experimental observations.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S1946427400041919

Tunneling Injection Quantum-Dot Lasers

AlxGa1−xAs‐GaAs quantum well heterostructure (QWH) laser diodes with much thinner upper confining layers (06, 045, 03, and 02 μm) than usual (1–2 μm) are demonstrated The diodes exhibit well behaved transverse far‐field patterns, low broad‐area pulsed threshold current densities, and high differential quantum efficiencies The diodes with thinnest upper confining layers, ∼02 μm, have broad‐area pulsed threshold current densities as low as Jth∼169 A/cm2 and a total external differential quantum efficiency ηT∼53% (∼500 μm long cavities) Stripe‐geometry (40 μm wide) laser diodes made from the crystals with 02 μm upper confining layers exhibit room‐temperature continuous (cw) threshold currents of 60 mA, output powers of ∼200 mW/facet (uncoated), and transverse far‐field patterns with a full angle half power (FAHP) of 48° Nonoptimized narrow‐stripe (∼4 μm) native‐oxide index‐guided laser diodes fabricated on the same 02 μm confining layer QWH crystal operate at pulsed thresholds as low as 9 mA and c

Nick Holonyak

Papers

Photosensitive Impurity-Assisted Tunneling in Au-Ge-Doped Ga 1-x Al x As p-n Diodes

Near‐Bandgap, Narrow‐Spectrum, Low‐Loss, Volume‐Excited GaAs Laser (77°K) with Time‐Uniform Output

Transition from edge to vertical cavity operation of tunnel contact algaas-gaas-ingaas quantum well heterostructure lasers

Tunneling Injection Quantum-Dot Lasers

Thin upper‐confining layer AlxGa1−xAs‐GaAs quantum well heterostructure laser diodes