A new mechanism of polarization switching and electron emission in ferroelectric cathodes is proposed. Surface flashover plasma of a ferroelectric origin was observed on a polar ferroelectric surface ͓D. Shur, G. Rosenman, and Ya. E. Krasik, Appl. Phys. Lett. 70, 574 ͑1997͔͒. Simultaneous measurements of switched charge and plasma density show that expanding surface plasma represents a dynamic switching electrode. Direct measurements of ion/electron emission currents and surface analysis implemented by different analytic tools indicate that electrons and ions from the surface plasma contribute to spontaneous polarization screening. The high energy of charged particles emitted from the surface plasma is ascribed to a high surface potential during polarization switching.

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The behavior of Ca/Sr(A1C14)2-SOClz + 7% (v/v) SO2 C-size cells during constant temperature discharge was studied. Fresh and stored (70~ for four weeks) cells were discharged inside a dedicated homemade calorimeter on two loads: 9.4 and 4fl or at 30 ~ and 55~ The heat generation rate (WT) of the cells (thermal power) during discharge was measured as a function of discharge time. There was no significant difference between fresh and stored cells with respect to heat generation during discharge. There was no loss in capacity during four weeks of storage at 70~ The following components of WT were calculated and plotted against discharge capacity: Ws, thermodynamic; Wp, polarization; W~, chemical. In many cases Wp was found to be the largest component of WT. The maximum corrosion rate of the calcium anode during discharge and its minimum Faradaic efficiency (e) were calculated from W~ on the assumption that anodic corrosion is the major component of W~. At 30~ e was about 0.9 while at 55~ it drops from 0.87 at 2 mAcm -2 to 0.84 at 4 mAcm -2. At 30~ the value of e, is similar to that of ti of the SEI of the calcium, indicating a similar corrosion mechanism for the calcium anode (both under OCV conditions and under load).

The calr chloride battery is a very promising candidate for high-energydensity and high-power-density applications ~1,2~ It has been found to be safer than high-rate lithium batteries. A laboratory prototype based on Ca(AICl4)~ electrolyte successfully resisted abuse charge and overdischarge tests, a partial compression test, short-circuit tests and heating up to 300oC ~1,2~ It can be discharged over a temperature range of -40 to +200~ ~ After being fully developed, it is expected to have a volumetric energy density greater than the Li-S0~ battery by 30~ or more;(i.e., 5.5Ahfor a C-size cell or 12Ah for a D-size cell).The major drawback of this Ca-TC cell has been rapid corrosion of the calcium anode (i.e., too short a shelf lifel.The calciumthionyl chloride cell is a SEI (Solid Electrolyte lnterphase) battery ~4~ The calcium anode is covered by a thin CaCI~ film which appears to be an anionic conductor. The properties of this film govern the quality and performance of the battery. The rapid selfdischarge of the calcium-thionyl chloride battery results from unsuitable properties of this SEI which may be: too high solubility in the electrolyte, non-compact structure, and a combination of a high anionic transference number (t_~l) and the large difference between the equivalent volume of CaCl= and that of calcium.

Racetrack-based modulator of increased linearity for optical links is presented and analyzed. The modulator is referred to as FLAME - Finer Linearity Amplitude Modulation Element. Linearity is improved via the introduction of a Double Injection approach. Large spurious-free-dynamic-range (SFDR) of 132dB·Hz(4/5) can thus be theoretically obtained. The FLAME is studied for silicon platform and requires small footprint size (100 × 50µm2) and low operation voltage, 2.5V. This makes the FLAME an appealing candidate for large scale integration in RF photonics.