Gas Source MBE Growth and Characterization of TlInGaAs/InP DH Structures for Temperature-independent Wavelength LD Application
Abstract : TlInGaAs/InP double-hetero (DH) structures were grown on (100) InP substrates by gas source MBE. The photoluminescence (PL) peak energy variation with temperature decreased with increasing Tl composition. For the DH with a Tl composition of 13%, the PL peak energy varied only slightly with temperature (-0.03 meV/K). This value corresponds to a wavelength variation of 0.04 nm/K and is much smaller than that of the lasing wavelength of InGaAsP/InP distributed feedback laser diodes (0.1 nm/K). TlInGaAs/InP light emitting diodes with 6% Tl composition were fabricated and the small temperature variation of the electroluminescence peak energy (-0.09 meV/K) was observed at the wavelength around 1.58 micrometers. The results are promising to realize the temperature-independent wavelength laser diodes, which are important in the wavelength division multiplexing (WDM) optical fiber communication systems.
Very small temperature-dependent band-gap energy in TlInGaAs/InP double heterostructures grown by gas-source molecular-beam epitaxy
TlInGaAs/InP double heterostructures (DHs) were grown on (100) InP substrates by gas-source molecular-beam epitaxy. Almost no occurrence of Tl interdiffusion at the InP/TlInGaAs heterointerface was confirmed. The photoluminescence (PL) intensity for the DH was approximately ten times stronger than that of the single heterostructure. The PL peak energy and its variation with temperature for the TlInGaAs/InP DH decreased with increasing Tl composition. For the DH with a Tl composition of 13%, the PL peak energy varied only slightly with temperature (0.03 meV/K). This value corresponds to a wavelength variation of 0.04 nm/K and is much smaller than that of the lasing wavelength of InGaAsP/InP distributed feedback laser diodes (0.1 nm/K).
On a New Subclass of p-Valent Close-to-Convex Mappings Defined by Two-Sided Inequality
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