Emission from quantum-dot high-ß microcavities: transition from spontaneous emission to lasing and the effects of superradiant emitter coupling.
Light Sci Appl
; 6(8): e17030, 2017 Aug.
Article
in En
| MEDLINE
| ID: mdl-30167281
ABSTRACT
Measured and calculated results are presented for the emission properties of a new class of emitters operating in the cavity quantum electrodynamics regime. The structures are based on high-finesse GaAs/AlAs micropillar cavities, each with an active medium consisting of a layer of InGaAs quantum dots (QDs) and the distinguishing feature of having a substantial fraction of spontaneous emission channeled into one cavity mode (high ß-factor). This paper demonstrates that the usual criterion for lasing with a conventional (low ß-factor) cavity, that is, a sharp non-linearity in the input-output curve accompanied by noticeable linewidth narrowing, has to be reinforced by the equal-time second-order photon autocorrelation function to confirm lasing. The paper also shows that the equal-time second-order photon autocorrelation function is useful for recognizing superradiance, a manifestation of the correlations possible in high-ß microcavities operating with QDs. In terms of consolidating the collected data and identifying the physics underlying laser action, both theory and experiment suggest a sole dependence on intracavity photon number. Evidence for this assertion comes from all our measured and calculated data on emission coherence and fluctuation, for devices ranging from light-emitting diodes (LEDs) and cavity-enhanced LEDs to lasers, lying on the same two curves one for linewidth narrowing versus intracavity photon number and the other for g(2)(0) versus intracavity photon number.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Type of study:
Prognostic_studies
Language:
En
Journal:
Light Sci Appl
Year:
2017
Document type:
Article
Affiliation country:
Germany
Publication country:
ENGLAND
/
ESCOCIA
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GB
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GREAT BRITAIN
/
INGLATERRA
/
REINO UNIDO
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SCOTLAND
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UK
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UNITED KINGDOM