Observation of spectral hole burning in photocurrent spectrum of InAs self-assembled quantum dots buried in pn-junction

Spectral hole burning of InAs self-assembled quantum dots (QDs) buried in pn-junction was observed for the first time. At 5 K, a narrow hole with width of less than 1 nm was observed and the hole depth increased as electric field increased. The hole was observed up to 40 K. The spectral hole is considered to be formed when tunneling rate of electrons becomes faster than recombination rate of electrons in a QD. Spectral hole width was well fitted with the convolution of Gaussian distribution of read light and Lorentzian distribution of absolute change taking into account homogeneous broadening of InAs QDs of ≤ 0.08 meV. Power-broadening of spectral hole was also observed with a writing light power of 20 mW.