Anomalous threshold current and time delays in indexhyphen;guided AlxGa1minus;xAshyphen;GaAs quantumhyphen;well lasers

摘要

Anomalous threshold current (Ith) variation with temperature and with pulse length, and large delays (up to 6 mgr;s) between excitation and the turnhyphen;on of stimulated emission are observed in indexhyphen;guided AlxGa1minus;xAshyphen;GaAs quantumhyphen;well heterostructure (QWH) lasers. These effects are found in laser diodes incorporating lsquo;lsquo;spikersquo;rsquo; doping layers (dgr;hyphen;Mg and dgr;hyphen;Se) within the QWH active region and that are fabricated via laserhyphen;assisted Si impurityhyphen;induced layer disordering. The introduction of contaminants during the localized melting and regrowth of the laserhyphen;induced layer disordering, and the effect of these impurities (or defects) with the active region lsquo;lsquo;spikersquo;rsquo; doping create traps. The traps causeIthto increase (not decrease) at lower temperature and at shorter current pulses, and cause time delay in turnhyphen;on of the operation.