Low-threshold laser medium utilizing semiconductor nanoshell quantum dots

Porotnikov, Dmitry; Diroll, Benjamin T.; Harankahage, Dulanjan; Obloy, Laura M; Yang, Mingrui; Cassidy, James; Ellison, Cole; Miller, Emily N.; Rogers, Spencer; Tarnovsky, Alexander N.; Schaller, Richard D.; Zamkov, Mikhail

doi:10.1039/d0nr03582c

Cited by 10 publications

(14 citation statements)

References 73 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Unfortunately, the synthetic challenges associated with the colloidal fabrication of these layered QDs have previously hindered their optical-gain performance. 31,32 Here, we demonstrate that semiconductor quantum shells fabricated via the colloidal epitaxy approach enable strong suppression of Auger recombination, resulting in the longest optical gain reported for colloidal semiconductor QDs to date (Table S1). The "inverted" architecture of quantum shells, featuring a CdS bulk −CdSe−CdS core−shell−shell composition, benefits from the repulsion of multiple excitons in a CdSe quantum-well layer (Figure 1a).…”

Section: Introductionmentioning

confidence: 75%

See 1 more Smart Citation

Quantum Shells Boost the Optical Gain of Lasing Media

et al. 2022

Self Cite

View full text Add to dashboard Cite

Auger decay of multiple excitons represents a significant obstacle to photonic applications of semiconductor quantum dots (QDs). This nonradiative process is particularly detrimental to the performance of QD-based electroluminescent and lasing devices. Here, we demonstrate that semiconductor quantum shells with an “inverted” QD geometry inhibit Auger recombination, allowing substantial improvements to their multiexciton characteristics. By promoting a spatial separation between multiple excitons, the quantum shell geometry leads to ultralong biexciton lifetimes (>10 ns) and a large biexciton quantum yield. Furthermore, the architecture of quantum shells induces an exciton–exciton repulsion, which splits exciton and biexciton optical transitions, giving rise to an Auger-inactive single-exciton gain mode. In this regime, quantum shells exhibit the longest optical gain lifetime reported for colloidal QDs to date (>6 ns), which makes this geometry an attractive candidate for the development of optically and electrically pumped gain media.

show abstract

Section: Introductionmentioning

confidence: 75%

“…These nanomaterials disperse multiple excitons across a spherical shell layer and, therefore, can support longer multiexciton lifetimes. Unfortunately, the synthetic challenges associated with the colloidal fabrication of these layered QDs have previously hindered their optical-gain performance. , …”

Section: Introductionmentioning

confidence: 99%

Quantum Shells Boost the Optical Gain of Lasing Media

et al. 2022

Self Cite

View full text Add to dashboard Cite

show abstract

“…The volume of QDQW nanoparticles was relatively small, which limited their ability to suppress exciton–exciton annihilation. , Subsequent modification of this geometry to include a large-size, wide-gap CdS core has produced the desired effect of Auger suppression, manifested through long-lived BX populations . Unfortunately, the synthetic challenges associated with the colloidal fabrication of these layered QDs have previously hindered their performance in optoelectronic applications. , …”

mentioning

confidence: 99%

“…48 Unfortunately, the synthetic challenges associated with the colloidal fabrication of these layered QDs have previously hindered their performance in optoelectronic applications. 49,50 High-quality quantum shells showing remarkable MX characteristics were recently realized through methods of colloidal epitaxy (Figure 1b,c). 38 In line with theoretical predictions, the large volume of the 2D CdSe shell layer caused a significant reduction in the rate of exciton−exciton annihilation, leading to near-record BX lifetimes (up to 10.5 ns, Figure 1a) and a large, ensemble-averaged BX QY (up to 81%, Figure 1a).…”

mentioning

confidence: 99%

Colloidal Quantum Shells: An Emerging 2D Semiconductor for Energy Applications

Cassidy¹,

Harankahage²,

Porotnikov³

et al. 2022

ACS Energy Lett.

Self Cite

View full text Add to dashboard Cite

Low-dimensional semiconductors hold strong promise for future energy applications. These nanomaterials are inexpensive to process and offer a broad spectrum of attractive quantum-mechanical properties. The notorious problem of low-dimensional nanostructures, however, lies in their limited performance under high energetic loads when more than one exciton per particle is created. Multiple excitons undergo fast annihilation, causing efficient roll-off in energy-intensive applications, including high-brightness light-emitting diodes, X-ray scintillators, and solar cells. In this Focus Review, we highlight an emerging type of low-dimensional semiconductors that make it possible to avoid such multiexciton (MX) energy losses. Recently demonstrated colloidal quantum shells benefit from the spatial separation of multiple excitons, which leads to extraordinary improvements to MX lifetimes and MX quantum yield. This makes the quantum shell morphology attractive for solution-processed optical and electrical devices. Here, we compare the optoelectronic properties of quantum shells against other low-dimensional semiconductors and discuss their emerging opportunities in solid-state lighting and energy-harvesting applications.

show abstract

“…Towards achieving this goal, advances are made in developing new optical gain materials, optimizing the pumping parameters. [5][6][7][8][9][10][11][12][13] Numerous organic, inorganic and biological optical gain materials have been reported, however there is a need for a characterization method to screen optical gain materials for specific applications in microdroplet liquid crystal lasers. Among the standard experimental techniques to characterize the optical gain of particular material, the amplified spontaneous emission (ASE) is by far the most popular method.…”

Section: Introductionmentioning

confidence: 99%

Optical gain and photostability of different laser dyes, quantum dots and quantum rods for liquid crystal micro lasers

Vellaichamy

Muševič

2022

Emerging Liquid Crystal Technologies XVII

View full text Add to dashboard Cite

Since the discovery of dye lasers, constant efforts are made towards developing optical gain materials with improved performance. Choosing an optical gain material for application in high-performance cholesteric liquid crystal micro-lasers requires a dedicated screening method. We employ Amplified Spontaneous Emission (ASE), and time-dependent fluorescence under pulsed excitation to study the optical gain parameter and photo-stability of laser dyes pyrromethene 567, pyrromethene 580, pyrromethene 597, pyrromethene 650, DCM, and Nile Red, dissolved in a nematic liquid crystal 5CB. Optical gain of CdSe/ZnS coreshell quantum dots dispersed in dodecene and CdSe/CdS coreshell quantum rods, dispersed in toluene was also measured and found to be much lower compared to the gain of fluorescent dyes. Pump energy and polarization dependence of ASE from dye molecules incorporated in the planar-aligned liquid crystal matrix is addressed. We determine the optical gain coefficient for different laser dyes by using the variable laser stripe illumination method using the small-signal gain model. The polarization dependence of ASE is determined in various geometries. We depict photostability from the half-life of emission intensity decay over a large number (10 6 -10 7 ) of repeated laser pulses for fluorescent dyes, quantum rods and quantum dots. We find that quantum rods and quantum dots are much more stable compared to fluorescent dyes. Based on the photophysical characterization, we select pyrromethene 567 and pyrromethene 597 as efficient laser dyes for nematic liquid crystal micro-lasers.

show abstract

Low-threshold laser medium utilizing semiconductor nanoshell quantum dots

Abstract: Colloidal semiconductor nanocrystals (NCs) represent a promising class of nanomaterials for lasing applications. Currently, one of the key challenges facing the development of high-performance NC optical gain media lies in...

Cited by 10 publications

References 73 publications

Quantum Shells Boost the Optical Gain of Lasing Media

Quantum Shells Boost the Optical Gain of Lasing Media

Colloidal Quantum Shells: An Emerging 2D Semiconductor for Energy Applications

Optical gain and photostability of different laser dyes, quantum dots and quantum rods for liquid crystal micro lasers

Contact Info

Product

Resources

About