Doped Metasurfaces: Optical Metasurfaces without Etched Structure based on Regular Spatially-doped Semiconductor and Compatible with General Functional Optical Films

Abstract As a new-type artificial two-dimensional planar array structure, metasurfaces can achieve the modulation of light field through a reasonable design and arrangement of sub-wavelength nano-structure units, which is expected to surpass conventional optical components theoretically. However, the metal or dielectric metasurfaces fabricated by etching process are often trapped in the problems including low focusing efficiency and difficult preparation, which greatly hinders their practical implementation. Here, an idea of “Doped metasurfaces” based on a spatial and regular doping of semiconductor thin films is proposed for the first time. This kind of metasurfaces without etched structure owns smooth and flat surface, allowing the addition of optical functional films like anti-reflection film, which thus gets their optical properties greatly improved and enriched on the basis of meta-structured focusing characteristics. In order to verify the effectiveness of this strategy, we simulate a doped metalens suitable for wide mid-infrared (MIR) range and design an anti-reflection film on it. It is shown that this designed MIR metalens possesses wide operating range, high transmittance and high focusing efficiency. The method proposed here provides a new idea or perspective for constructing metasurfaces devices compatible with traditional optical thin films.

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Effect of Hydrogen Treatment on Room -Temperature Electric-Field Induced Properties in Narrow-Gap ZnCdHgTe Thin Films

MRS Proceedings ◽

10.1557/proc-813-h4.3 ◽

2004 ◽

Vol 813 ◽

Author(s):

Galina M. Khlyap ◽

Petro G. Sydorchuk ◽

Jacek Polit

Keyword(s):

Thin Films ◽

Room Temperature ◽

Hydrogen Treatment ◽

Narrow Gap ◽

Glass Substrates ◽

Semiconductor Thin Films ◽

Visible Wavelength Range ◽

Current Voltage ◽

Before And After ◽

First Time

ABSTRACTThe effect of hydrogen treatment on room temperature electric properties of narrow-gap semiconductor thin films ZnxCdyHg1−z−yTe (0 < x < 0.50, 0.20 < y < 0.40) is investigated for the first time. ZnCdHgTe films of 2 – 5 [.proportional]m thickness were grown on glass substrates by pulsed laser deposition technique. As-grown films were thermally treated in the flow of molecular H2 at 200°C during 24 hours. Comparison between electric characteristics measured before and after hydrogenation showed sufficient changes of the film resistance and appearance of photosensitivity in the visible wavelength range. Study of current-voltage characteristics of the films revealed appearance and significant change of diode-like properties.

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British prison projects: the Hard Labour Bill and the Penitentiary Act

Law Review of Kyiv University of Law ◽

10.36695/2219-5521.1.2020.13 ◽

2020 ◽

pp. 74-80

Author(s):

Olena Sokalska

Keyword(s):

Revolutionary War ◽

Practical Implementation ◽

Local Initiative ◽

The Public ◽

Key Points ◽

New Type ◽

Care Requirements ◽

First Time ◽

Detention Facilities ◽

Hard Labour

The article analyzes the English prison projects: the Hard Labour Bill 1778 and the Penitentiary Act 1779. The author identified the reasons for their creation, sources, key points and their impact on the formation of penitentiary systems. The American Revolutionary War made it impossible relocation of convicted criminals to the colony. His Majesty's Government had to rush to find a replacement for transportation. In the mid-70s of 18 century there were attempts to develop the foundations of new types of punishment that would replace transportation. Such an alternative would hard labor in special Houses of Hard Labor and Penitentiary Houses. The application of punishment by hard labour to criminals sentenced to transportation is developed in the Hulks Act 1776, the Hard Labour Bill 1778 and the Penitentiary Act 1779. The Hard Labour Bill and the Penitentiary Act were not about reforming prisons, but about developing a system of execution and serving a new type of punishment – imprisonment combined with hard labor. The Hard Labor Bill for the first time enshrined the norms that, in 30-40 years, became the basis of the Pennsylvania system, the Auburn system, the progressive system: solitary confinement, the division of convicts into classes, the correction of the offender with the active participation of chaplain, the system disciplinary offence and sanction, initiation of post-penitentiary care, requirements for prison staff, control and supervision of prison activity by the public and judges. The Hard Labor Bill has not been approved by Parliament. It has been slightly redesigned. The idea of a system of Houses of Hard Labor across the country had to be abandoned. Instead, William Blackstone proposed experimental Penitentiary Houses. It was approved in the Penitentiary Act 1779. An analysis of the main provisions of the Penitentiary Act shows that at least part of the regulation of the Penitentiary Houses and their conditions of detention were based on the Hard Labor Bill. Although the ambitious idea of creating a network of prisons throughout the country has been abandoned, Penitentiary Act 1779 has retained the general philosophy of imprisonment in combination with hard labor. Despite the lack of practical implementation, the 1779 Penitentiary Act was essential to further improve the operation of existing detention facilities and build new prisons throughout the country, but as a local initiative rather than a centralized reform.

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Quantitative Image Analysis of Fractal-like Thin Films of Organic Semiconductors

10.26434/chemrxiv.6223610.v1 ◽

2018 ◽

Author(s):

Weikun Zhu ◽

Erfan Mohammadi ◽

Ying Diao

Keyword(s):

Thin Film ◽

Thin Films ◽

Image Analysis ◽

Fractal Dimension ◽

Organic Semiconductors ◽

Film Growth ◽

Electronic Device ◽

Significant Control ◽

Semiconductor Thin Films ◽

Two Parameters

Morphology modulation offers significant control over organic electronic device performance. However, morphology quantification has been rarely carried out via image analysis. In this work, we designed a MATLAB program to evaluate two key parameters describing morphology of small molecule semiconductor thin films: fractal dimension and film coverage. We then employ this program in a case study of meniscus-guided coating of 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C<sub>8</sub>-BTBT) under various conditions to analyze a diverse and complex morphology set. The evolution of morphology in terms of fractal dimension and film coverage was studied as a function of coating speed. We discovered that combined fractal dimension and film coverage can quantitatively capture the key characteristics of C<sub>8</sub>-BTBT thin film morphology; change of these two parameters further inform morphology transition. Furthermore, fractal dimension could potentially shed light on thin film growth mechanisms.

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Annealing Behavior with Thickness Hindered Nucleation in Small-Molecule Organic Semiconductor Thin Films

Crystal Growth & Design ◽

10.1021/acs.cgd.9b00213 ◽

2019 ◽

Vol 19 (7) ◽

pp. 3777-3784

Author(s):

Jakub Rozbořil ◽

Katharina Broch ◽

Roland Resel ◽

Ondřej Caha ◽

Filip Münz ◽

...

Keyword(s):

Thin Films ◽

Small Molecule ◽

Organic Semiconductor ◽

Annealing Behavior ◽

Semiconductor Thin Films

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Charge Trapping in Mixed Organic Donor-Acceptor Semiconductor Thin Films

Advanced Materials ◽

10.1002/adma.201403198 ◽

2014 ◽

Vol 26 (45) ◽

pp. 7555-7560 ◽

Cited By ~ 14

Author(s):

Shota Nunomura ◽

Xiaozhou Che ◽

Stephen R. Forrest

Keyword(s):

Thin Films ◽

Charge Trapping ◽

Semiconductor Thin Films ◽

Donor Acceptor

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A Relationship Between the Factor Indivisibility and the Output Elasticity of the Indivisible Factor

Studies in Microeconomics ◽

10.1177/2321022220985160 ◽

2021 ◽

pp. 232102222098516

Author(s):

Dipankar Das

Keyword(s):

Production Function ◽

Limit Point ◽

Mathematical Proof ◽

Wage Equation ◽

Marginal Value ◽

Output Elasticity ◽

New Type ◽

First Time ◽

Jel Classifications

The paper puts forth a notion and derives a special type of production function where labour is an indivisible factor and is in the integer space. Thus, Newtonian calculus is not an appropriate method of deriving the marginal value because limit point does not exist. This shows that indivisibility determines the output elasticity. In the first part, the paper propounds a notion regarding how indivisibility determines curvature of the production function. In the second part, the paper incorporates the findings within a production function and derives a new type accordingly. Moreover, it formally derives the standard wage equation considering all the entitlements of labour, namely (a) normal wages, (b) interest and (c) rent of ability. So far, no such mathematical proof is there to support this wage composition. This paper, for the first time, derives this wage equation considering indivisibility of labour. JEL Classifications: J23, J24, J31, D24, C61, E24, L8

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