Temperature dependence of photoluminescence from high-density GaAs/(GaAs)4(AlAs)2 quantum wires grown on (775)B-oriented GaAs substrates by molecular beam epitaxy

Temperature dependence of photoluminescence (PL) was investigated for high-density and highly uniform GaAs/(GaAs)(4) (AlAs)(2) quantum wires (QWRs) grown on a (7 7 5)B GaAs substrate by molecular beam epitaxy, which are naturally formed in an average 2.1 nm width GaAs/(GaAs)(4)(AlAs)(2) quantum well (QW) with a corrugated upper interface (a lateral period of 12 nm and a vertical amplitude of 1.2 nm) and a flat lower interface. As temperature increases in the range of T greater than or equal to 60 K, PL intensity of the (7 7 5)B GaAs/(GaAs)(4)(AlAs)(2) QWRs decreases more slowly and is several times larger compared with that of a GaAs/(GaAs)4(A1As)z QW simultaneously grown on a (1 0 0) GaAs substrate, indicating reduction of the nonradiative decay process of exicitons in the (7 7 5)B QWRs. The full width at half maximum of the PL peak from the (7 7 5)B QWRs is almost independent of temperature above 60 K, while that of the (1 0 0) QW increases in proportion to about k(B)T above 50 K. These results strongly indicate the one-dimensional characteristics of the (7 7 5)B QWRs as theoretically predicted. (C) 1998 Elsevier Science B.V. All rights reserved.