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The negative luminescent properties of HgCdTe photodiodes having peak emission at a wavelength of 7.6 micrometer, as a function of temperature and applied bias is investigated. The findings show that the small currents needed to drive the diodes, together with their long-wavelength luminescence, make them suitable for a range of device applications.

A cavity-length study is used for determining the temperature variation of the internal loss and gain per unit current density in a ten-stage interband cascade laser with an emission wavelength of 4.05 [micro]m. The strong decrease of the pain per unit current density is due to the dramatic shortening of the Auger lifetime.dauger

Focuses on theoretical modeling of photonic-crystal distributed-feedback (PCDFB) lasers for the midwave infrared. Capability of the PDCFB laser to provide near-diffraction-limited, spectrally pure sources of midwave-infrared radiation; Analysis of second-order and first-order optically pumped PCDFB lasers with 'W' active regions.

Midinfrared “W” quantum-well diode lasers with reduced turn-on voltages are reported. Devices with coated facets operated in continuous-wave mode up to 195 K, where the emission wavelength was 3.56 μm. At 78 K, the threshold current density was 67 A/cm[sup 2], the maximum output power was 198 mW, and the slope efficiency was 106 mW/A. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We investigate broad-stripe photonic-crystal distributed-feedback lasers emitting at λ=4.4 μm. The beam quality improves dramatically when a laser ablation technique is used to eliminate parasitic Fabry–Pérot-like modes, by inducing loss in the regions adjoining the pump stripe. Even though the peak of the gain spectrum never fully aligns with the grating resonance, for pulsed pumping the output beam is essentially diffraction limited up to a stripe width of 150 μm, and remains no worse than six times the diffraction limit for stripes as broad as 400 μm. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Investigates the field induced deformation of molecular geometry in electroclinic liquid crystal. Bimodal distribution of smectic A layer in KN125; Evaluation of the triangular deformation model; Importance of considering distribution of molecular directors within a stripe domain.

Investigates the Auger lifetimes for InAs, InAsSb, IAsSb-InAlAsSb quantum wells. Correlation of the Auger rate at 77 Kelvin with the proximity to resonance between the energy gap and the split-off gap; Reduction of the Auger coefficient in the alloy with decreasing temperature; Rise of the Auger coefficient of the quantum well with decreasing temperature.