Title :
Evidence of interdot carrier coupling in In/sub 0.4/Ga/sub 0.6/As self-assembled quantum dots
Author :
Urayama ; Norris, Theodore B. ; Kamath, K. ; Bhattacharya, Pallab
Author_Institution :
Centre for Ultrafast Opt. Sci., Michigan Univ., Ann Arbor, MI, USA
Abstract :
Summary form only given. Femtosecond differential transmission (DT) spectroscopy of In/sub 0.4/Ga/sub 0.6/ quantum dots (QD) pumped resonantly with a narrow band pulse shows an extremely rapid spreading of the energy spectrum, indicating carrier coupling among dots of different sizes. This rapid spectral spread has been observed and attributed to carrier-carrier scattering in quantum well systems. However, in In/sub 0.4/Ga/sub 0.6/As QDs, our DT measurements, taken as a function of carrier density, point to a rapid carrier energy spread based on tunneling.
Keywords :
III-V semiconductors; gallium arsenide; high-speed optical techniques; indium compounds; semiconductor quantum dots; time resolved spectroscopy; In/sub 0.4/Ga/sub 0.6/; In/sub 0.4/Ga/sub 0.6/As QDs; In/sub 0.4/Ga/sub 0.6/As self-assembled quantum dots; carrier coupling; carrier density; energy spectrum; femtosecond differential transmission; interdot carrier coupling; narrow band pulse; o carrier-carrier scattering; rapid carrier energy spread; rapid spectral spread; time resolved spectroscopy; tunneling; Charge carrier density; Couplings; Density measurement; Energy measurement; Narrowband; Particle scattering; Quantum dots; Resonance; Spectroscopy; Tunneling;
Conference_Titel :
Quantum Electronics and Laser Science Conference, 2000. (QELS 2000). Technical Digest
Conference_Location :
San Francisco, CA, USA
Print_ISBN :
1-55752-608-7
