Showing posts with label M. Ashida. Show all posts
Showing posts with label M. Ashida. Show all posts

Monday, April 22, 2019

Abstract-Visualization of the internal field in the GaAs-based solar cell under its operating condition with Terahertz radiation


K. Miyagawa, M. Nagai, C. Kim,  H. Akiyama, Y. Kanemitsu, M. Ashida

https://ieeexplore.ieee.org/document/8510084

We demonstrated the visualization of the internal field in a GaAs-based solar cell under its operating condition with evaluating the first half-period of the terahertz (THz) wave emitted by the simultaneous excitation with the weak ultrashort optical pulse and continuous light. We observed the reduction of the internal field with increasing the intensity of the continuous light, which is relevant to the solar cell performance.

Thursday, March 24, 2016

Abstract-Electrical transport properties of (La,Pr,Ca)MnO3 nanowires investigated using terahertz time domain spectroscopy



The electrical transport properties of a 100-nm-width (La,Pr,Ca)MnOnanowire sample were investigated using terahertz (THz) time domain spectroscopy. When the electric field of incident THz pulses was parallel to the nanowires, we obtained their intrinsic THz conductivity. The temperature-dependent dcconductivity and metallic fraction were simultaneously estimated by analyzing the THz conductivity using a metal-insulatorcomposite model. The evaluated dc conductivity closely reproduced that measured by electrical probe measurement. The metallic fraction showed the evolution of electric domains from the metallic state at temperatures below 100 K to the insulating state at temperatures above 150 K through a coexistence region, which was in consistence with the phase-separated scenario.