wherein, the second voltage application electrode comprises {HEAD ~ a transparent electrode} formed over a surface of the second phase changing {TAIL ~ layer} and a voltage supply portion with a resistance that is lower than that of the transparent electrode, and 
wherein , the second voltage application electrode comprises { HEAD ~ a transparent electrode } formed over a surface of the second phase changing { TAIL ~ layer } and a voltage supply portion with a resistance that is lower than that of the transparent electrode , and
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH