Lee, Hyun Seok Cheong, Byung-ki Lee, Taek Sung Jeong, Jeung-Hyun Lee, Suyoun Kim, Won Mok Kim, Donghwan 2024-01-21T01:05:35Z 2024-01-21T01:05:35Z 2021-09-02 2007-04 0021-4922 https://pubs.kist.re.kr/handle/201004/134505 An experiment was conducted to investigate the origin of the nonlinear optical characteristics of crystalline Ge2Sb2Te5 and Ge-doped SbTe thin films which have been demonstrated to have the capability of a superresolution readout. By means of the real-time measurement of the electrical resistance combined with concurrent optical reflectance/transmittance measurement during pulsed laser irradiation of varying power, it was found that the absorption coefficients of these films decrease with. increasing laser power, accompanied most probably by an increase in the carrier concentration. This finding may be understood in light of the saturable absorption due to band filling by thermally assisted photoexcited carriers. This has been previously proposed as an important cause of the superresolution effect of PbTe, which belongs to the chalcogemide degenerate semiconductors such as the GeSbTe materials under study. English INST PURE APPLIED PHYSICS RESOLUTION DISK MECHANISM READOUT MEMORY Origin of nonlinear optical characteristics of crystalline Ge-Sb-Te thin films for possible superresolution effects Article 10.1143/JJAP.46.L277 1 JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS, v.46, no.12-16, pp.L277 - L279 JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS 46 12-16 L277 L279 scie scopus 000246234400006 2-s2.0-34547888319 Physics, Applied Physics Article RESOLUTION DISK MECHANISM READOUT MEMORY optical data storage superresolution (SR) PbTe Ge2Sb2Te5 Ge-doped SbTe nonlinear optical effect saturable absorption free carrier