Electric field induced optical second harmonic generation (EFISHG) measurement at the laser wavelength of 1000nm and 1080nm is conducted to investigate the carrier behaviors in PCPDTBT and PC71BM bulk heterojunction organic solar cells (OSCs). We find that the response time for electrode charging through the external circuit in +1V and -1V are almost identical but the response time for the Maxwell-Wagner-type interfacial charging is different in +1V or -1V. We find that the accumulated charges of PC71BM is more than the accumulated charges of PCPDTBT and consequently affects the efficiency of the bulk heterojunction OSCs.

By using electric-field-induced optical second-harmonic generation (EFISHG) measurement, we investigated interfacial carrier behavior in organic solar cells (OSCs) with a blocking layer of bathocuproine (BCP). Results evidently showed that the Maxwell-Wagner type excess charges accumulate on both pentacene/C60 and C60/BCP interfaces. Also, the measurement under short-circuit and open-circuit conditions clearly showed the different photo-induced carrier behaviors in the OSCs devices. Our work proved that the dielectric nature of OSCs dominates the operation of our OSCs and the EFISHG technique is very effective to characterize the dielectric performance of the OSCs.

In this paper, we present a new design to support multicasting in an ATM switches, called the Singlecast Stuffed Multicast Advanced Processing (SSMAP) ATM switch, which can transmit multicast traffic effectively. The SSMAP ATM switch consists of two cell operation parts, a multicast operation part and a singlecast operation part. This structure is designed so as to increase the efficiency of packet forwarding by allowing singlecast cells to use the resources that remain unused during multicast traffic handling. Furthermore, we propose new multicast scheduling methods using the SSMAP ATM switch. We evaluate the characteristics of the SSMAP ATM switch and multicast scheduling methods by computer simulations, and demonstrate their validity.