Optical Rectenna: Generating power from heat

By Fouad Sabry

What Is Optical Rectenna

A rectenna that functions with either visible or infrared light is referred to as an optical rectenna. The transformation of electromagnetic waves into direct current electricity is accomplished using a rectenna, which is a circuit that consists of both an antenna and a diode. An optical rectenna would function in the same manner as a radio or microwave rectenna, but it would convert infrared or visible light into electricity instead of radio waves or microwaves. Rectennas have been in use for a long time.

How You Will Benefit

(I) Insights, and validations about the following topics:

Chapter 1: Optical rectenna

Chapter 2: Photodiode

Chapter 3: Band gap

Chapter 4: Gallium arsenide

Chapter 5: Rectenna

Chapter 6: Wide-bandgap semiconductor

Chapter 7: Indium phosphide

Chapter 8: Photodetector

Chapter 9: Photovoltaic effect

Chapter 10: Thermophotovoltaic

Chapter 11: Hybrid solar cell

Chapter 12: Third-generation photovoltaic cell

Chapter 13: Multi-junction solar cell

Chapter 14: Carbon nanotubes in photovoltaics

Chapter 15: Organic solar cell

Chapter 16: Solid

Chapter 17: Shockley-Queisser limit

Chapter 18: Transparent conducting film

Chapter 19: Plasmonic solar cell

Chapter 20: Solar cell research

Chapter 21: Sun-free photovoltaics

(II) Answering the public top questions about optical rectenna.

(III) Real world examples for the usage of optical rectenna in many fields.

(IV) 17 appendices to explain, briefly, 266 emerging technologies in each industry to have 360-degree full understanding of optical rectenna' technologies.

Who This Book Is For

Professionals, undergraduate and graduate students, enthusiasts, hobbyists, and those who want to go beyond basic knowledge or information for any kind of optical rectenna.

• Language: English
• Publisher: One Billion Knowledgeable
• Release date: Oct 15, 2022

Book preview

Copyright

Optical Rectenna Copyright © 2022 by Fouad Sabry. All Rights Reserved.

All rights reserved. No part of this book may be reproduced in any form or by any electronic or mechanical means including information storage and retrieval systems, without permission in writing from the author. The only exception is by a reviewer, who may quote short excerpts in a review.

Cover designed by Fouad Sabry.

This book is a work of fiction. Names, characters, places, and incidents either are products of the author’s imagination or are used fictitiously. Any resemblance to actual persons, living or dead, events, or locales is entirely coincidental.

Bonus

You can send an email to [e-mail] with the subject line Optical Rectenna: Generating power from heat, and you will receive an email which contains the first few chapters of this book.

Fouad Sabry

Visit 1BK website at

www.1BKOfficial.org

Preface

Why did I write this book?

The story of writing this book started on 1989, when I was a student in the Secondary School of Advanced Students.

It is remarkably like the STEM (Science, Technology, Engineering, and Mathematics) Schools, which are now available in many advanced countries.

STEM is a curriculum based on the idea of educating students in four specific disciplines — science, technology, engineering, and mathematics — in an interdisciplinary and applied approach. This term is typically used to address an education policy or a curriculum choice in schools. It has implications for workforce development, national security concerns and immigration policy.

There was a weekly class in the library, where each student is free to choose any book and read for 1 hour. The objective of the class is to encourage the students to read subjects other than the educational curriculum.

In the library, while I was looking at the books on the shelves, I noticed huge books, total of 5,000 pages in 5 parts. The books name is The Encyclopedia of Technology, which describes everything around us, from absolute zero to semiconductors, almost every technology, at that time, was explained with colorful illustrations and simple words. I started to read the encyclopedia, and of course, I was not able to finish it in the 1-hour weekly class.

So, I convinced my father to buy the encyclopedia. My father bought all the technology tools for me in the beginning of my life, the first computer and the first technology encyclopedia, and both have a great impact on myself and my career.

I have finished the entire encyclopedia in the same summer vacation of this year, and then I started to see how the universe works and to how to apply that knowledge to everyday problems.

My passion to the technology started mor than 30 years ago and still the journey goes on.

This book is part of The Encyclopedia of Emerging Technologies which is my attempt to give the readers the same amazing experience I had when I was in high school, but instead of 20th century technologies, I am more interested in the 21st century emerging technologies, applications, and industry solutions.

The Encyclopedia of Emerging Technologies will consist of 365 books, each book will be focused on one single emerging technology. You can read the list of emerging technologies and their categorization by industry in the part of Coming Soon, at the end of the book.

365 books to give the readers the chance to increase their knowledge on one single emerging technology every day within the course of one year period.

Introduction

How did I write this book?

In every book of The Encyclopedia of Emerging Technologies, I am trying to get instant, raw search insights, direct from the minds of the people, trying to answer their questions about the emerging technology.

There are 3 billion Google searches every day, and 20% of those have never been seen before. They are like a direct line to the people thoughts.

Sometimes that’s ‘How do I remove paper jam’. Other times, it is the wrenching fears and secret hankerings they would only ever dare share with Google.

In my pursuit to discover an untapped goldmine of content ideas about Optical Rectenna, I use many tools to listen into autocomplete data from search engines like Google, then quickly cranks out every useful phrase and question, the people are asking around the keyword Optical Rectenna.

It is a goldmine of people insight, I can use to create fresh, ultra-useful content, products, and services. The kind people, like you, really want.

People searches are the most important dataset ever collected on the human psyche. Therefore, this book is a live product, and constantly updated by more and more answers for new questions about Optical Rectenna, asked by people, just like you and me, wondering about this new emerging technology and would like to know more about it.

The approach for writing this book is to get a deeper level of understanding of how people search around Optical Rectenna, revealing questions and queries which I would not necessarily think off the top of my head, and answering these questions in super easy and digestible words, and to navigate the book around in a straightforward way.

So, when it comes to writing this book, I have ensured that it is as optimized and targeted as possible. This book purpose is helping the people to further understand and grow their knowledge about Optical Rectenna. I am trying to answer people’s questions as closely as possible and showing a lot more.

It is a fantastic, and beautiful way to explore questions and problems that the people have and answer them directly, and add insight, validation, and creativity to the content of the book – even pitches and proposals. The book uncovers rich, less crowded, and sometimes surprising areas of research demand I would not otherwise reach. There is no doubt that, it is expected to increase the knowledge of the potential readers’ minds, after reading the book using this approach.

I have applied a unique approach to make the content of this book always fresh. This approach depends on listening to the people minds, by using the search listening tools. This approach helped me to:

Meet the readers exactly where they are, so I can create relevant content that strikes a chord and drives more understanding to the topic.

Keep my finger firmly on the pulse, so I can get updates when people talk about this emerging technology in new ways, and monitor trends over time.

Uncover hidden treasures of questions need answers about the emerging technology to discover unexpected insights and hidden niches that boost the relevancy of the content and give it a winning edge.

The building block for writing this book include the following:

(1) I have stopped wasting the time on gutfeel and guesswork about the content wanted by the readers, filled the book content with what the people need and said goodbye to the endless content ideas based on speculations.

(2) I have made solid decisions, and taken fewer risks, to get front row seats to what people want to read and want to know — in real time — and use search data to make bold decisions, about which topics to include and which topics to exclude.

(3) I have streamlined my content production to identify content ideas without manually having to sift through individual opinions to save days and even weeks of time.

It is wonderful to help the people to increase their knowledge in a straightforward way by just answering their questions.

I think the approach of writing of this book is unique as it collates, and tracks the important questions being asked by the readers on search engines.

Acknowledgments

Writing a book is harder than I thought and more rewarding than I could have ever imagined. None of this would have been possible without the work completed by prestigious researchers, and I would like to acknowledge their efforts to increase the knowledge of the public about this emerging technology.

Dedication

To the enlightened, the ones who see things differently, and want the world to be better -- they are not fond of the status quo or the existing state. You can disagree with them too much, and you can argue with them even more, but you cannot ignore them, and you cannot underestimate them, because they always change things... they push the human race forward, and while some may see them as the crazy ones or amateur, others see genius and innovators, because the ones who are enlightened enough to think that they can change the world, are the ones who do, and lead the people to the enlightenment.

Epigraph

A rectenna that functions with either visible or infrared light is referred to as an optical rectenna. The transformation of electromagnetic waves into direct current electricity is accomplished using a rectenna, which is a circuit that consists of both an antenna and a diode. An optical rectenna would function in the same manner as a radio or microwave rectenna, but it would convert infrared or visible light into electricity instead of radio waves or microwaves. Rectennas have been in use for a long time.

Table of Contents

Copyright

Bonus

Preface

Introduction

Acknowledgments

Dedication

Epigraph

Table of Contents

Chapter 1: Optical rectenna

Chapter 2: Photodiode

Chapter 3: Band gap

Chapter 4: Rectenna

Chapter 5: Wide-bandgap semiconductor

Chapter 6: Indium phosphide

Chapter 7: Quantum efficiency

Chapter 8: Photodetector

Chapter 9: Photovoltaic effect

Chapter 7: District heating

Chapter 11: Hybrid solar cell

Chapter 12: Nanophotonics

Chapter 13: Third-generation photovoltaic cell

Chapter 14: Carbon nanotubes in photovoltaics

Chapter 15: Organic solar cell

Chapter 16: Sandwich panel

Chapter 17: Physical neural network

Chapter 18: Transparent conducting film

Chapter 19: Plasmonic solar cell

Chapter 20: Solar cell research

Chapter 21: Sun-free photovoltaics

Epilogue

About the Author

Coming Soon

Appendices: Emerging Technologies in Each Industry

Chapter 1: Optical rectenna

A rectenna (also known as a rectifying antenna) that operates with visible or infrared light is referred to as an optical rectenna. The transformation of electromagnetic waves into direct current electricity is accomplished using a rectenna, which is a circuit that consists of both an antenna and a diode. Rectennas have been in use for a long time for receiving radio waves or microwaves; however, an optical rectenna would function in the same manner but with infrared or visible light, converting it into electricity.

Despite the fact that optical rectennas are conceptually comparable to regular (radio and microwave) rectennas, it is a far more difficult task to actually construct an optical rectenna. Because the frequency of light is so high—hundreds of terahertz for visible light—there are only a select few varieties of specialized diodes that can flip rapidly enough to correct it. This presents a hurdle. Because antennas typically have a size that is comparable to a wavelength, the production of a very small optical antenna necessitates the use of a complex nanotechnology technique. This is still another obstacle. The fact that an optical antenna is often extremely small means that it normally absorbs relatively little power. As a result, they tend to create a tiny voltage in the diode, which in turn leads to low diode nonlinearity and, as a result, poor efficiency. This presents a third difficulty. Because of these and other obstacles, optical rectennas have only been utilized in demonstrations in the lab up to this point. These lab demonstrations generally include intensely concentrated laser light, which generates a negligible but quantifiable amount of power.

In spite of this, there is optimism that arrays of optical rectennas might one day prove to be an effective method of transforming sunlight into electric power, hence creating solar electricity at a rate that is higher than that of traditional solar cells. Robert L. Bailey made the first suggestion for the concept back in 1972. It is uncertain at this time if they will ever be as cost-effective or efficient as traditional solar cells.

It is possible to refer to an optical rectenna when using the word nantenna, which is short for nano-antenna., alternatively, an optical antenna on its own.

Currently, Idaho National Laboratories has designed an optical antenna to absorb wavelengths in the range of 3–15 μm.

(see Figure 1).

An electromagnetic wave energy converter developed by Robert Bailey and James C. Fletcher was awarded a patent in the United States in 1973 with the number US 3760257. The patented apparatus was comparable to optical rectennas used in the present day. The patent describes the application of a diode of the kind described by [Ali Javan] in the IEEE Spectrum, October, 1971, page 91, to wit, a metal cat's whisker with a diameter of 100 nanometers that is attached to a metal surface that has a thin oxide layer covering it. It was stated that Javan was successful in reversing 58 THz of infrared radiation. In 1974, T. In 1996, Guang H. Lin disclosed resonant light absorption by a manufactured nanostructure and rectification of light with frequencies in the visible range. Gustafson and coauthors proved that these sorts of devices could correct even visible light to DC current. Despite this, research on optical rectenna is still being conducted.

These carbon nanotube rectenna devices suffer from a lack of air stability, which is the fundamental disadvantage of these devices. Calcium was used as a semitransparent top electrode in the device structure that was initially reported by Cola. This was done because the low work function of calcium (2.9 eV) in comparison to the work function of MWCNTs (5 eV) creates the diode asymmetry that is necessary for optical rectification. However, metallic calcium is very volatile when exposed to air and oxidizes in a short amount of time. In order to avoid the malfunction of the measuring instrument, the measurements had to be carried out inside of a glovebox in a sterile atmosphere. Because of their restricted use in the real world, the gadgets.

Later on, Cola and his colleagues overcame the difficulties caused by the instability of the device by altering the construction of the diode to include many layers of oxide. In 2018, they announced the development of the first air-stable optical rectenna as well as advances in efficiency.

This new generation of rectenna was able to accomplish its air-stability because to some customization done to the quantum tunneling barrier of the diode.

Rather of relying on a single dielectric insulator, They demonstrated that increasing the number of oxide layers with varying compositions may improve diode performance by altering the diode tunneling barrier.

Through the use of oxides with varying electron affinities, Regardless of the difference in work function between the two electrodes, the electron tunneling may be made to create an asymmetric diode response if the conditions are right.

By using layers of Al2O3 and HfO2, The asymmetric response of a diode was enhanced more than tenfold with the construction of a double-insulator diode known as a metal-insulator-insulator-metal (MIIM) diode. This was accomplished without the need of a low work function. calcium, silver, which is not affected by air, eventually took its position as the primary metal.

In the future, attempts are going to be made to increase the device's efficiency by looking into new materials, modifying the MWCNTs and the insulating layers to stimulate conduction at the interface and lower resistances inside the structure.

The theory that behind optical rectennas is, for all intents and purposes, equivalent to that which underpins conventional (radio or microwave) rectennas. When light strikes the antenna, it sets off a chain reaction that causes the electrons within the antenna to flow back and forth at the same frequency as the light. This is because the entering electromagnetic wave has a fluctuating electric field that is causing this effect. In the circuit that makes up the antenna, the flow of electrons produces an alternating current (AC). The alternating current (AC) has to be rectified before it can be changed into direct current (DC), and this is commonly done using a diode. After that, the DC current that was produced may be utilized to provide power to an external load. According to the basic microwave antenna theory, the resonant frequency of antennas (the frequency that results in lowest impedance and hence greatest efficiency) scales linearly with the physical size of the antenna. This is the frequency that results in the highest efficiency. Because of this, a rectifying antenna has to be on the order of hundreds of nm in size in order for it to be an efficient electromagnetic collector in the sun spectrum.

When considering optical rectennas, there are a number of complexities that come up as a result of the simplifications that are utilized in conventional rectifying antenna theory. Because practically all of the current is carried close to the surface of the wire at frequencies exceeding infrared, the effective cross sectional area of the wire is reduced, which results in an increase in the wire's resistance. The term skin effect has also been used to refer to this phenomenon. Even if Ohm's law, in its generalized vector version, is still valid, the I-V characteristics could give the impression that they are no longer ohmic. This is despite the fact that Ohm's law is still applicable.

Diodes that are used in larger scale rectennas are unable to function at THz frequencies without suffering a significant loss of power, which is another difficulty that arises when scaling down.

The great potential efficiency of optical rectennas is often cited as one of the devices' most compelling selling points.

When compared to the efficiency of single junction solar cells from a theoretical perspective (30 percent ), It would seem that optical rectennas have a major advantage in this situation.

However, Both of these efficiencies are determined based on a variety of different presumptions.

The calculations for the rectenna are based on the use of the Carnot efficiency of solar collectors, which leads to a number of assumptions being made.

The effectiveness of the Carnot cycle, η, is given by

{\displaystyle \eta =1-{\frac {T_{\text{cold}}}{T_{\text{hot}}}}}

where Tcold is the temperature of the cooler body and Thot is the temperature of the warmer body.

Energy must be converted in a way that is both effective and efficient, It is necessary that there be a large temperature disparity between the two bodies.

R.

L.

Bailey claims that rectennas are not limited by Carnot efficiency, Photovoltaics, on the other hand, are.

However, This assertion is not supported by any evidence that he provides.

Furthermore, When the same assumptions that were used to derive the theoretical efficiency of 85 percent for rectennas are applied to single junction solar cells, the results are significantly different, The efficiency of single junction solar cells is also better than 85 percent from a theoretical standpoint.

The fact that arrays of optical rectennas can be constructed to absorb any frequency of light is perhaps the most obvious