DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal. If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the "Taverne" license above, please follow below link for the End User Agreement:

Ultracold atomic gases have been used extensively in recent years to realize textbook examples of condensed matter phenomena. Recently, phase transitions to ordered structures have been predicted for gases of highly excited, "frozen" Rydberg atoms. Such Rydberg crystals are a model for dilute metallic solids with tunable lattice parameters, and provide access to a wide variety of fundamental phenomena. We investigate theoretically how such structures can be created in four distinct cold atomic systems, by using tailored laser-excitation in the presence of strong Rydberg-Rydberg interactions. We study in detail the experimental requirements and limitations for these systems, and characterize the basic properties of small crystalline Rydberg structures in one, two and three dimensions.

Document VersionPublisher's PDF, also known as Version of Record (includes final page, issue and volume numbers) Please check the document version of this publication:• A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. ABSTRACTThe non-uniform presence of shunting defects is a significant cause of poor reproducibility across large-area solar cells, or from batch-to-batch for small area cells, but the most commonly used value for shunt parameterisation (the shunt resistance) fails to identify the cause for shunting. Here, the use of equivalent circuit models to describe dark current-voltage characteristics of ZnO:Al/i-ZnO/CdS/CIGS/Mo devices in order to understand shunting behaviour is evaluated. Simple models, with a single shunt pathway, were tested but failed to fit experimental data, whereas a more sophisticated model developed here, which includes three shunting pathways, yielded excellent agreement throughout the temperature range of 183-323 K. The temperature dependence of fitting parameters is consistent with known physical models. Activation energies and contact barriers are determined from the model, and extracted diode factors are unique across the voltage range. A case study is presented whereby the model is used to diagnose poor reproducibility for CIGS devices (efficiency~3-14% across a 100 cm 2 plate). It's shown that lower efficiencies correlated with greater prevalence of Ohmic and non-Ohmic shunt currents, which may form due to pinholes in absorber and buffer layers respectively, whereas the quality of the main junction was constant for all cells (diode factor~1.5-2). Electron microscopy confirmed the presence of ZnO:Al/i-ZnO/Mo and ZnO:Al/CIGS/Mo regions, supporting the mult...

In silicon heterojunction solar cells, the main opportunities for efficiency gain lie in improvements of the front-contact layers. Therefore, the effect of transparent conductive oxides (TCOs) on the a-Si:H passivation performance has been investigated for Al-doped zinc oxide (ZnO:Al) layers made by atomic layer deposition (ALD). It is shown that the ALD process, as opposed to sputtering, does not impair the chemical passivation. However, the field-effect passivation is reduced by the ZnO:Al. The resulting decrease in low injection-level lifetime can be tuned by changing the ZnO:Al doping level (carrier density = 7 × 10 19 -7 × 10 20 cm −3 ), which is explained by a change in the TCO workfunction. Additionally, it is shown that a ∼10-15 nm ALD ZnO:Al layer is sufficient to mitigate damage to the a-Si:H by subsequent sputtering, which is correlated to ALD film closure at this thickness.

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Document VersionPublisher's PDF, also known as Version of Record (includes final page, issue and volume numbers) Please check the document version of this publication:• A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication Citation for published version (APA):Knoops, H. C. M., Loo, van de, B. W. H., Smit, S., Ponomarev, M., Weber, J. W., Sharma, K., ... Creatore, M. (2015). Optical modeling of plasma-deposited ZnO films : electron scattering at different length scales. Journal of Vacuum Science and Technology. A: Vacuum, Surfaces, and Films, 33, 021509-1/13. DOI: 10.1116/1.4905086 General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Articles you may be interested in Carrier mobility of highly transparent conductive Al-doped ZnO polycrystalline films deposited by radio-frequency, direct-current, and radio-frequency-superimposed direct-current magnetron sputtering: Grain boundary effect and scattering in the grain bulk J. Appl. Phys. 117, 045304 (2015) In this work, an optical modeling study on electron scattering mechanisms in plasma-deposited ZnO layers is presented. Because various applications of ZnO films pose a limit on the electron carrier density due to its effect on the film transmittance, higher electron mobility values are generally preferred instead. Hence, insights into the electron scattering contributions affecting the carrier mobility are required. In optical models, the Drude oscillator is adopted to represent the free-electron contribution and the obtained optical mobility can be then correlated with the macroscopic material properties. However, the influence of scattering phenomena on the optical mobility depends on the considered range of photon energy. For example, the grain-boundary scattering is generally not probed by means o...

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The passivation of Si by Al 2 O 3 /ZnO stacks, which can serve as passivated tunneling contacts or heterojunctions in silicon photovoltaics, was investigated. It was demonstrated that stacks with Al 2 O 3 thicknesses >3 nm lead to lower surface recombination velocities (S eff,max < 4 cm s −1 ) on n-and p-type Si than single-layer Al 2 O 3 films for a wide range of ZnO thicknesses and irrespective of Al-doping of the ZnO. Stacks with an Al 2 O 3 thickness of 1-2 nm were found to combine reasonable surface passivation (S eff,max = 100-700 cm s −1 ) with sufficiently high tunneling current densities (10-300 mA cm −2 at 700 mV).