ABSTRACT
Ultrafast differential transmission spectroscopy is used to explore temperature-dependent carrier dynamics in an InAs/InGaAs quantum dots-in-a-well heterostructure. Electron-hole pairs are optically injected into the three dimensional GaAs barriers, after which we monitor carrier relaxation into the two dimensional InGaAs quantum wells and the zero dimensional InAs quantum dots by tuning the probe photon energy. We find that carrier capture and relaxation are dominated by Auger carrier-carrier scattering at low temperatures, with thermal emission playing an increasing role with temperature. Our experiments provide essential insight into carrier relaxation across multiple spatial dimensions.
Subject(s)
Arsenicals/chemistry , Gallium/chemistry , Indium/chemistry , Quantum Dots , Equipment Design , Equipment Failure Analysis , TemperatureSubject(s)
Foot Diseases/diagnosis , Heel , Pain/etiology , Aged , Humans , Male , Middle Aged , Occupational Diseases/diagnosis , Posture , PressureSubject(s)
Urachus/abnormalities , Adult , Age Factors , Child, Preschool , Cysts/congenital , Cysts/surgery , Female , Fistula/diagnosis , Fistula/surgery , Humans , Infant, Newborn , Male , Umbilicus/abnormalities , Urachus/surgerySubject(s)
Foot Dermatoses/diagnosis , Adult , Foot Dermatoses/complications , Foot Dermatoses/pathology , Heel , Humans , Male , Pain/etiologyABSTRACT
In the connective tissue, diffusely scattered phenoloxidase containing cells (PO-cells) can be found by histochemical methods. The same cells were demonstrated in a recurrent malignant melanoma of the skin and in its lymph node metastases. The theory is proposed that PO-cells are the stem cells of malignant melanoma in contrary to the common view that melanoma derives from the melanocytes of the stratum cyclindricum of the epidermis. The occurrence and distribution of PO-cells in the rat give a good explanation for the appearance of metastasis within different organs and tissues.
