Giant fluctuations of radiation intensity of two-dimensional electrons in double quantum wells

Giant fluctuations of the recombination-radiation intensity of two-dimensional electrons were studied in double quantum wells with different well and barrier widths in the regime of the integer quantum Hall effect. It was found that the giant fluctuations of photoluminescence intensity in double quantum wells with a narrow barrier (l<150 Å) occur in a narrow magnetic-field interval, where the sum of electron concentrations in both wells corresponds to the integer filling factors 4, 8, and 12. It was established that, under these conditions, the coefficient C ₁₂ of correlation between the radiation intensities from different wells is close to unity. It is shown that, as the barrier width increases (l>200 Å), the coefficient C ₁₂ decreases, changes sign, and goes to zero at l=400 Å.