This paper describes the method used to evaluate single-mode optical connectors under consideration for military
avionics platforms. This testing is described in terms of the appropriate fiber optics test procedures (FOTPs)
from the TIA/EIA-455 series.
This paper reports the radiation tolerance of small form factor multimode optical transceivers designed for extended temperature and vibration environments. The transceivers are based on specifically designed VCSELs and PIN photodiodes and packaged such that the transceiver functions over an extended temperature range (beyond -40 to +85°C) without affecting performance or dynamic range. These transceivers are capable of multi-Gigabit per second transmission with bit error ratio of less than 1e-12 in non-irradiated conditions. To characterize these transceivers, we have measured their response to dose rate, total dose, and neutron fluence environments. For the dose rate test, we report the upset, latch-up, and burnout thresholds of the transceiver. In the total dose test, we measure the total dose level that does not significantly affect the transceiver and characterize the degradation for increasing total dose levels. For the neutron fluence test, we measure the fluence level that does not significantly affect the transceiver and characterize the degradation for increasing fluence levels. With this radiation data on the performance limits and penalties of the transceiver, high speed fiber optic links may now be considered for platforms previously off limits due to their irradiated environments.
The DF and PLDMR of triplet exciton and polaron dynamics in (pi) -conjugated materials and devices is reviewed, and the significance of various processes involving these long-lived excitations is considered. These include the generation of singlet excitons by triplet-triplet annihilation, which leads to DF, and nonradiative quenching of such singlets by polarons or triplet excitons. The clear differences between the roles of these processes in (pi) -conjugated polymers vs small molecules and their implications for organic light emitting devices are discussed.
We have studied (alpha) -sexithiophene ((alpha) -6T) films by photoinduced absorption (PA) and optically-detected magnetic resonance (ODMR). The PA of the disordered film is composed of two polaron PA bands and one bipolaron PA band, each with its own vibronic side bands. Measurements of an ordered film indicate that charge conjugation symmetry is broken and the polaron energy bands are shifted. The spin-1/2 ODMR of this film has a Gaussian lineshape with an 8 Gauss width. The PA of the ordered film shows no evidence for polarons. The bipolaron band is clearly split, indicating violation of charge conjugation symmetry. The ODMR of this film is significantly broader than that of the disordered film, which may be evidence for spin-spin interaction between paired charged excitations.