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Heterostructure and Q-factor engineering for low-threshold and persistent nanowire lasing.

ABSTRACT: Continuous room temperature nanowire lasing from silicon-integrated optoelectronic elements requires careful optimisation of both the lasing cavity Q-factor and population inversion conditions. We apply time-gated optical interferometry to the lasing emission from high-quality GaAsP/GaAs quantum well nanowire laser structures, revealing high Q-factors of 1250?±?90 corresponding to end-facet reflectivities of R?=?0.73?±?0.02. By using optimised direct-indirect band alignment in the active region, we demonstrate a well-refilling mechanism providing a quasi-four-level system leading to multi-nanosecond lasing and record low room temperature lasing thresholds (~6??J?cm-2?pulse-1) for III-V nanowire lasers. Our findings demonstrate a highly promising new route towards continuously operating silicon-integrated nanolaser elements.

SUBMITTER: Skalsky S

PROVIDER: S-EPMC7078256 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Heterostructure and Q-factor engineering for low-threshold and persistent nanowire lasing.

Skalsky Stefan S Zhang Yunyan Y Alanis Juan Arturo JA Fonseka H Aruni HA Sanchez Ana M AM Liu Huiyun H Parkinson Patrick P

Light, science & applications 20200317

Continuous room temperature nanowire lasing from silicon-integrated optoelectronic elements requires careful optimisation of both the lasing cavity Q-factor and population inversion conditions. We apply time-gated optical interferometry to the lasing emission from high-quality GaAsP/GaAs quantum well nanowire laser structures, revealing high Q-factors of 1250 ± 90 corresponding to end-facet reflectivities of R = 0.73 ± 0.02. By using optimised direct-indirect band alignment ...[more]

PMID: 32194957

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