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

(b) Write out the equations for the time dependence of ρ11, ρ22, ρ12 and ρ21 assuming that a light field interaction V = -μ12Ee iωt + c.c. couples only levels |1> and |2>, and that the excited levels exhibit spontaneous decay. (8 marks) (c) Under steady-state conditions, find the ratio of populations in states |2> and |3>. (3 marks) (d) Find the slowly varying amplitude ̃ ρ 12 of the polarization ρ12 = ̃ ρ 12e iωt . (6 marks) (e) In the limiting case that no decay is possible from intermediate level |3>, what is the ground state population ρ11(∞)? (2 marks) 2. (15 marks total) In a 2-level atom system subjected to a strong field, dressed states are created in the form |D1(n)> = sin θ |1,n> + cos θ |2,n-1> |D2(n)> = cos θ |1,n> sin θ |2,n-1>

The Quantum Theory of Light

Characteristic order over distances of 15–30 A is indicated by various experiments on covalent non-crystalline solids. The data are reviewed and detailed structural models are developed containing 30–1000 atoms.

Topology of covalent non-crystalline solids II: Medium-range order in chalcogenide alloys and ASi(Ge)

In the past decade, attosecond technology has opened up the investigation of ultrafast electronic processes in atoms, simple molecules, and solids. Here, we report the application of isolated attosecond pulses to prompt ionization of the amino acid phenylalanine and the subsequent detection of ultrafast dynamics on a sub–4.5-femtosecond temporal scale, which is shorter than the vibrational response of the molecule. The ability to initiate and observe such electronic dynamics in polyatomic molecules represents a crucial step forward in attosecond science, which is progressively moving toward the investigation of more and more complex systems.

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Ultrafast electron dynamics in phenylalanine initiated by attosecond pulses

This letter presents a type of infrared detector named the nBn detector. The nBn design essentially eliminates Shockley-Read-Hall generation currents. The result is greatly reduced dark current and noise, compared to other midwave infrared detectors, such as p-n photodiodes. This enables the nBn to operate at background-limited infrared photodetection conditions at significantly higher temperatures than conventional midwave infrared detectors and have greater detectivity near room temperature. The nBn is demonstrated in InAs and InAsSb materials, exhibiting cutoff wavelengths of 3.4 and 4.2μm, respectively.

nBn detector, an infrared detector with reduced dark current and higher operating temperature

Previous theories to explain the variation of photoconductivity upon saturation of electron spin resonance, as observed by Lepine in silicon, predict an effect 10 to 100 times smaller than experiment. In the present model we show that, due to the shorter lifetime of electron-hole pairs in singlet configuration, the steady state spin distribution shows a surplus of triplet pairs. Saturation of resonance restores the random distribution, resulting in a shortening of the recombination time. The relative variation can be as large as 10 %, and is field independent as confirmed by experiment.

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Explanation of the large spin-dependent recombination effect in semiconductors

A new femtosecond pulse characterization, named self-referenced spectral interferometry, is introduced. Based on linear spectral interferometry, the reference pulse is self created from the pulse being characterized. This self reference results from pulse shaping optimization and non-linear temporal filtering.

Self-referenced spectral interferometry

It is shown that heat treatment in a hydrogen plasma of pure amorphous silicon films prepared by UHV evaporation yields a material with no observable dangling bond ESR signal. This material has electrical properties similar to films prepared by a glow‐discharge decomposition of silane but a lower hydrogen content as deduced from ir absorption data.

Hydrogenation of evaporated amorphous silicon films by plasma treatment

A three-stage, 1-kHz amplifier system delivering pulses shorter than 10 fs with a peak power in excess of 0.3 TW is reported. Passive and active spectral intensity and phase control allows the preservation of a bandwidth of 120 nm (FWHM) to as high as multimillijoule energy levels and temporal compression of the broadband pulses close to their Fourier limit. The system is scalable to peak powers well beyond 1 TW and holds promise for substantially advancing the state of the art of coherent laboratory soft-x-ray sources.

Sub-10-fs, terawatt-scale Ti:sapphire laser system.

We report giant, nonlinear optical rectification in asymmetric quantum wells weakly coupled by an intermediate potential barrier. This phenomenon originates from (i) macroscopic displacements (30 nm) of carriers during optical transitions and (ii) large storage times of excited electrons because of a slow transfer mechanism between the wells (≊6 ps at 77 K). The resulting rectification coefficient is 1.62×10−3 m/V per well, more than six orders of magnitude higher than in bulk GaAs. These structures really behave as giant ‘‘quasimolecules’’ optimized for infrared optical nonlinearities and their use may be envisioned for a new class of infrared detectors.

Daniel Kaplan

Papers

Explanation of the large spin-dependent recombination effect in semiconductors

Self-referenced spectral interferometry

Hydrogenation of evaporated amorphous silicon films by plasma treatment

Sub-10-fs, terawatt-scale Ti:sapphire laser system.

Giant nonlinear optical rectification at 8–12 μm in asymmetric coupled quantum wells