In:
Japanese Journal of Applied Physics, IOP Publishing, Vol. 35, No. 2S ( 1996-02-01), p. 1311-
Abstract:
We have realized injection lasers based on InAs–GaAs and InGaAs–GaAs quantum pyramids (QPs) with a lateral size ranging from 80 to 140 Å. The structures with relatively small dots (∼80 Å) exhibit properties predicted earlier for quantum dot (QD) lasers such as low threshold current densities (below 100 Acm -2 ) and ultrahigh characteristic temperatures ( T 0 =350–425 K). For operation temperatures above 100–130 K, T 0 decreases and the threshold current density increases (up to 0.95–3.3 kAcm -2 at room temperature) due to carrier evaporation from QPs. Larger InAs QPs (∼140 Å) providing better carrier localization exhibit saturation of the ground-state emission and enhanced nonradiative recombination rate at high excitation densities. The radiative lifetime shows a weak dependence on the dot size in the range 80–140 Å being close to ∼1.8–2 ns, respectively. A significant decrease in radiative lifetime is realized in vertically coupled quantum dots formed by a QP shape-transformation effect. The final arrangement corresponds to a three-dimensional tetragonal array of InAs islands inserted in a GaAs matrix each composed of several vertically merging InAs parts. We achieved injection lasing in such an array for the first time.
Type of Medium:
Online Resource
ISSN:
0021-4922
,
1347-4065
DOI:
10.1143/JJAP.35.1311
Language:
Unknown
Publisher:
IOP Publishing
Publication Date:
1996
detail.hit.zdb_id:
218223-3
detail.hit.zdb_id:
797294-5
detail.hit.zdb_id:
2006801-3
detail.hit.zdb_id:
797295-7
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