Welcome to Ishida Laboratory

Welcome to Ishida Laboratory

Department of Electronics and Materials Science

Research : Semiconductor and quantum well physics

IV-VI compound semiconductor mid-infrared lasers

Physics of thermoelectrics and materials

 

1. We observed strong interband absorption in 7- 25 μm wavelength region from PbTe/PbSnTe-based type-II superlattice, which has potential application to long wavelength interband cascade lasers. 

2. We prepared optically pumped short-cavity PbSrS/PbS DH laser on Si substrate for single-mode tunable operation of 3 μm laser, which has future application to single-mode tunable diode lasers.  ( A. Ishida, et al., Appl. Phys. Lett. 111, 161104 (2017).)

3. Thermoelectric properties and thermoelectric conversion efficiencies of IV-VI semiconductors. Thermoelectric properties and conversion efficiency were calculated theoretically. (A. Ishida, et al., Materials Today Proc. 5, pp.10187-10194 (2018).)

   Seebeck coefficient and thermoelectric conversion efficiency of highly p-type PbTe were calculated considering heavy hole valleys along Σ axes, and the calculated results were compared with the theoretical data in the papers by Heremans et al. (Science 321, 554 (2008)), Y. Pei et al. (Nature 473, pp.66 (2011)), Zhang et al. ( JACS 134, pp.10031 (2012)), and J. Vineis, et al.(Phys. Rev. B 77, 235202(2008)), and good agreements were obtaind between theoretical and experimental values.

4. High efficiency and high power PbSrS/PbS MQW VECSEL (vertical external cavity surface emitting laser) was prepared on BaF2(111) substrate, and the origin of high efficiency laser operation was clarified.