دانلود کتاب سخنرانی‌هایی در مورد نظریه میدان الکترومغناطیسی -مروری جامع

This set of lecture notes is from my teaching of ECE 604 Electromagnetic Field Theory, since Fall of 2018, at Purdue University in West Lafayette, Indiana. It is intended for entry-level graduate students. Because different universities have different undergraduate requirements in electromagnetic field theory, this is a course intended to “level the playing field”. From this point onward, hopefully, all students will have the fundamental background in electromagnetic field theory needed to take advanced-level courses and do research at Purdue. In developing this course, I have drawn heavily upon knowledge of our predecessors in this area. I have listed many of the textbooks and papers used in the reference list. Being a practitioner in this field for over forty years, I have seen electromagnetic theory impacting modern technology development unabated. Despite its age, the set of Maxwell’s equations has had an enduring legacy and continues to be important, from statics to optics to extreme-ultra-violet (EUV) light, from classical to quantum, and from sub-nanometer (subatomic) length scales to galactic length scales. The applications of electromagnetic technologies have also been tremendously wide-ranging, including geophysical exploration, remote sensing, electrical power systems, renewable and clean energy, biomedical engineering, optics, photonics integrated circuits, computer circuit design, computer systems, quantum computers, quantum communications, and many more. Electromagnetic field theory is not everything, but it remains an indispensable component of modern technology developments. The challenge in teaching this course is on how to teach over 150 years of knowledge in one semester; this is, of course, mission impossible! To do this, we use the traditional wisdom of engineering education: distill the knowledge, make it as simple as possible, and teach the fundamental big ideas in one short semester. Because of this, you may find the flow of the lectures erratic and rapid. Sometimes, I feel the need to touch on certain big ideas before moving on, resulting in the choppiness of the curriculum. Also, in this course, I exploit mathematical “homomorphism” as much as possible to simplify the teaching. After years of practicing in this area, I find that many complex and advanced concepts become simpler if mathematical homomorphism is exploited between the advanced concepts and simpler ones. An example of this is on waves in layered media. The problem is homomorphic to the transmission line problem: hence, using transmission line theory, one can simplify the derivations of some complicated formulas. A large part of modern applied electromagnetic technologies is based on heuristics: this is difficult to teach, as it relies on physical insight and experience. Modern commercial software has reshaped this landscape: the field of math-physics modeling through numerical simulations, known as computational electromagnetics (CEM), has made rapid advances in recent years. Many cutandtry laboratory experiments, based on heuristics, have been replaced by cut-and-try computer experiments, which are a lot cheaper. An exciting modern development is the role of electromagnetics and Maxwell’s equations in quantum technologies. We will connect Maxwell’s equations to quantum electromagnetics toward the end of this course. This is a challenge, as it has never been done before in an entry-level course to my knowledge.10 The first vacuum tube computer, ENIAC, was built around 1945. After that, in the 1950s, a series of vacuum tube plus transistor computers were built, including the ILLIAC series at the University of Illinois. Those computers can fill a whole room. After some 70 years, with the exponential growth of nanotechnologies, we can now carry a pocket-size cell phone packed with billions of transistors. A change in modus operandi is that engineering designs are now done increasingly more with software to reduce cost rather than cut-and-try experiments. Thus, an important field of CEM has emerged in recent years. Virtual prototyping and digital twins rely greatly on the fidelity of simulation software: engineering designs can be done with software rather than hardware. In fact, 95 percent of a computer chip design is now done with software simulation, greatly reducing the design cost. Unfortunately, we can only spend two lectures on CEM to convey some of the big ideas to the students of electromagnetics. The devil is in the details in the implementation of these big ideas, which can be pursued in other courses.