Highly Charged Excitons and Biexcitons in Type-II Core/Crown Colloidal Nanoplatelets

Llusar, Jordi; Climente, Juan I.

doi:10.1021/acs.jpcc.2c00827

Cited by 9 publications

(14 citation statements)

References 50 publications

(95 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…415 Theoretical models predict that biexciton binding energies can be tuned by varying the relative sizes of CdSe/CdTe core/crowns. 416 Utilizing single-particle spectroscopy, relative biexciton quantum yields were measured. The ratio of antibunched features (from single exciton recombination) to the bunched (biexciton) feature at low excitation fluence is interpreted in these experiments as a measure of the relative QY of biexciton.…”

Section: Nonlinear Absorption and Second Harmonic Generation Numerous...mentioning

confidence: 99%

“…In Type II, CdSe/CdTe core/crown systems, repulsive biexcitons with blueshifted emission and binding energies as high as 200 meV are observed . Theoretical models predict that biexciton binding energies can be tuned by varying the relative sizes of CdSe/CdTe core/crowns . Utilizing single-particle spectroscopy, relative biexciton quantum yields were measured.…”

Section: Synthesis and Structure Of Nplsmentioning

confidence: 99%

See 1 more Smart Citation

2D II–VI Semiconductor Nanoplatelets: From Material Synthesis to Optoelectronic Integration

Diroll

Güzeltürk

et al. 2023

Chem. Rev.

View full text Add to dashboard Cite

The field of colloidal synthesis of semiconductors emerged 40 years ago and has reached a certain level of maturity thanks to the use of nanocrystals as phosphors in commercial displays. In particular, II−VI semiconductors based on cadmium, zinc, or mercury chalcogenides can now be synthesized with tailored shapes, composition by alloying, and even as nanocrystal heterostructures. Fifteen years ago, II−VI semiconductor nanoplatelets injected new ideas into this field. Indeed, despite the emergence of other promising semiconductors such as halide perovskites or 2D transition metal dichalcogenides, colloidal II−VI semiconductor nanoplatelets remain among the narrowest room-temperature emitters that can be synthesized over a wide spectral range, and they exhibit good material stability over time. Such nanoplatelets are scientifically and technologically interesting because they exhibit optical features and production advantages at the intersection of those expected from colloidal quantum dots and epitaxial quantum wells. In organic solvents, gram-scale syntheses can produce nanoparticles with the same thicknesses and optical properties without inhomogeneous broadening. In such nanoplatelets, quantum confinement is limited to one dimension, defined at the atomic scale, which allows them to be treated as quantum wells. In this review, we discuss the synthetic developments, spectroscopic properties, and applications of such nanoplatelets. Covering growth mechanisms, we explain how a thorough understanding of nanoplatelet growth has enabled the development of nanoplatelets and heterostructured nanoplatelets with multiple emission colors, spatially localized excitations, narrow emission, and high quantum yields over a wide spectral range. Moreover, nanoplatelets, with their large lateral extension and their thin short axis and low dielectric surroundings, can support one or several electron−hole pairs with large exciton binding energies. Thus, we also discuss how the relaxation processes and lifetime of the carriers and excitons are modified in nanoplatelets compared to both spherical quantum dots and epitaxial quantum wells. Finally, we explore how nanoplatelets, with their strong and narrow emission, can be considered as ideal candidates for pure-color light emitting diodes (LEDs), strong gain media for lasers, or for use in luminescent light concentrators.

show abstract

Section: Nonlinear Absorption and Second Harmonic Generation Numerous...mentioning

confidence: 99%

Section: Synthesis and Structure Of Nplsmentioning

confidence: 99%

2D II–VI Semiconductor Nanoplatelets: From Material Synthesis to Optoelectronic Integration

Diroll

Güzeltürk

et al. 2023

Chem. Rev.

View full text Add to dashboard Cite

show abstract

“…These methods were extended to make NCs of different shapes, resulting in colloidal CdTe nanorods, nanowires, nanotubes and tetrapods. , However, the colloidal synthesis of CdTe NPLs and the studies conducted on them have lagged behind. Compared to their Cd chalcogenide counterparts, CdTe NPLs showcase widely separated and distinct light-hole (LH) and heavy-hole (HH) features, a narrow, tunable emission line width, and fast PL decay lifetimes among other interesting characteristics and can have a considerable impact in optoelectronics − and photon management technologies. − Coupling these with a large absorption coefficient and high atomic numbers (48 and 52 for Cd and Te, respectively), they present themselves as materials with enormous prospects in radiation detection.…”

mentioning

confidence: 99%

“…However, CdTe NPLs are shown to suffer from low PL quantum yields (PLQYs) resulting from lattice defects which have pulled them down in the priority of research compared to CdSe NPLs. As a result, work on CdSe and CdS NPLs , has been replicated only partially with CdTe, , limiting its use in combination with other Cd chalcogenides such as CdSe and CdS in the form of core–shell, core–crown , and core–barrier–crown heterostructures . To date, two - dimensional CdTe nanostructures have been reported in the form of zincblende structured NPLs, wurtzite structured nanoribbons and CdTe nanosheets. , In 2013, Pedetti et al optimized the synthesis protocol for the colloidal synthesis of CdTe NPLs with zincblende structure, yielding NPL populations of different thicknesses defined with atomic precision.…”

mentioning

confidence: 99%

Optical and Scintillation Properties of Record-Efficiency CdTe Nanoplatelets toward Radiation Detection Applications

et al. 2022

View full text Add to dashboard Cite

Colloidal CdTe nanoplatelets featuring a large absorption coefficient and ultrafast tunable luminescence coupled with heavy-metal-based composition present themselves as highly desirable candidates for radiation detection technologies. Historically, however, these nanoplatelets have suffered from poor emission efficiency, hindering progress in exploring their technological potential. Here, we report the synthesis of CdTe nanoplatelets possessing a record emission efficiency of 9%. This enables us to investigate their fundamental photophysics using ultrafast transient absorption, temperature-controlled photoluminescence, and radioluminescence measurements, elucidating the origins of exciton-and defectrelated phenomena under both optical and ionizing excitation. For the first time in CdTe nanoplatelets, we report the cumulative effects of a giant oscillator strength transition and exciton fine structure. Simultaneously, thermally stimulated luminescence measurements reveal the presence of both shallow and deep trap states and allow us to disclose the trapping and detrapping dynamics and their influence on the scintillation properties.

show abstract

“…[189] These exchange interactions, in NPLs, such as CO and CC, may be particularly relevant and may also become increased due to the strong quantum and dielectric confinement, in the out-of-plane direction, combined with the weak lateral confinement , over the in-plane directions, seen in these types of nanostructures. In a typical CdSe-based CO NPL with large lateral dimensions: first, the energy spacing between ground and first excited states is about 10 meV [92,112,190] and secondly, when applying magnetic fields perpendicularly to the NPL plane, considerable diamagnetic shifts are enabled through the radial part of the first term in equations (1.34) and (1.35). The mean squared radius, x 2 + y 2 in both equation 1.34 and 1.35, increases with the lateral dimensions of the NPL, leading to significant diamagnetic shifts.…”

Section: Magnetic Propertiesmentioning

confidence: 99%

Elastic, Electrostatic and Magnetic Properties in Colloidal Quantum Wells

Camarelles¹

View full text Add to dashboard Cite

Resum iv Acronyms ixI express my special thanks to my supervisor, Dr. Juan I. Climente (Nacho), whose ability and knowledge were pure gold for my learning process. Most of the things I know, not only during this dissertation but also along my chemistry degree, are because of him. Personally, his dedication and deftness to teach me during all these past years and especially his guidance during this doctoral program were priceless. Undoubtedly, I can be sure that Nacho can be considered for me, let's say, as my academic father.I also thank my tutor, Prof. Dr. Josep Planelles. It goes without saying that he is like the tribal shaman or the oracle of the QQ Group. His years of experience and his physical intuition make him, without a doubt, the cornerstone of this wonderful group. His advice was unvaluable.Of course, I would like to thank David (in a few months Dr. David Macias). He was a great colleague and is naturally a greater person. From him, I take his calm in stressful situations.In addition, I strongly thank my parents for helping me financially support this doctorate. Unfortunately, in Spain, governments apparently do not have much interest in science. This fact affects a large number of outstanding potential researchers who, due to different factors, are unable to pay for resources, dissemination of their results, or even worse, for doctorate enrolment.Finally, I would like to thank my partner Mical from the bottom of my heart for being fully supportive of me when all of these ups and downs that involve a doctorate programme arose. Thanks to her I could get away from that workaholic instinct, which should be shut off in some cases to preserve good mental health.

show abstract

Highly Charged Excitons and Biexcitons in Type-II Core/Crown Colloidal Nanoplatelets

Cited by 9 publications

References 50 publications

2D II–VI Semiconductor Nanoplatelets: From Material Synthesis to Optoelectronic Integration

2D II–VI Semiconductor Nanoplatelets: From Material Synthesis to Optoelectronic Integration

Optical and Scintillation Properties of Record-Efficiency CdTe Nanoplatelets toward Radiation Detection Applications

Elastic, Electrostatic and Magnetic Properties in Colloidal Quantum Wells

Contact Info

Product

Resources

About