Japanese Journal of Applied Physics

Tunable Slow Light of 1.3 µm Region in Quantum Dots at Room Temperature

Hideki Gotoh, Shu‐Wei Chang, S. L. Chuang, Hiroshi Okamoto, Yasuo Shibata

Published Apr 1, 2007• 7 citations

Abstract

We report tunable slow light (slowlight) in the 1.3 µm region in quantum dots (QDs) observed at room temperature. The light transmission times are measured by the counter-propagating pump-and-probe method in waveguides with InAs QDs as active regions. The maximum slowdown factor is 2.5 for a 500-µm-long sample. This corresponds to a 2.5 times longer propagation time in the waveguide. The slowdown can be well controlled by tuning the pump beam. This pump power dependence of the slowdown factor agrees well with theoretical predictions obtained by coherent population oscillation (CPO). We also report a method that realizes larger slow light effects.

DOI: 10.1143/jjap.46.2369

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