Optical pumping as artificial doping in quantum dots-in-a-well infrared photodetectors

Quantum structure based infrared detector research and development within Acreo’s centre of excellence IMAGIC

“…as concerns operating temperature for detectors of similar wavelength response. For undoped InAs/In 0.15 Ga 0.85 As/GaAs DWELL IPs, peak responsivities of 25 mA/W at an operating temperature of 77 K have been measured [7] and by using optical pumping as artificial doping, a peak responsivity of 250 mA/W has been predicted [8]. This is in fairly good agreement with the DWELL IPs demonstrated by Gunapala et al [9] for DWELL IPs with normal incidence detection.…”

Influence of built-in charge on photogeneration and recombination processes in InAs/GaAs quantum dot solar cells

“…This effect is known for InAs/GaAs low-dimensional heterostructures as artificial doping, where the IR response is increased by resonant optical pumping due to an enhanced intraband transition rate from the localized states of the QDs to the conduction band states of the matrix [40].…”

Strong Enhancement of Solar Cell Efficiency Due to Quantum Dots with Built-In Charge

“…The measurements of the photoresponse to IR portion of solar radiation (Figure ) and its comparison with the photoresponse to the entire solar spectrum (Figure ) demonstrate that even under a low-power radiation the short- and long-wavelength contributions are not independent and the total photocurrent is significantly larger than the sum of two separate contributions. Let us note that this effect is known for IR QD photodetectors, where the IR response is significantly enhanced by the optical pumping . In ref , optical pumping was limited by relatively low energy quanta, which could generate only electron–hole pairs localized in the QDs.…”

“…Let us note that this effect is known for IR QD photodetectors, where the IR response is significantly enhanced by the optical pumping . In ref , optical pumping was limited by relatively low energy quanta, which could generate only electron–hole pairs localized in the QDs. It was concluded that in this case the optical pumping is equivalent to the doping of QDs.…”