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Preface
The dawn of nonlinear electronics was ushered during the 1960s by a Cambrianesque explosion of newly minted two-terminal electronic devices, bearing such
intimidating monikers as Esaki diode, Josephson junction, varactor diode, thyristor,
impact ionization avalanche transit time (IMPATT) diode, Gunn diode, and ovonic
threshold switch. Trained in the old school of linear circuit analysis, hordes of
electronics engineers were awed and shocked upon witnessing a parade of such
strongly nonlinear and dynamical electronic devices unfolding at such a breathless
rate. To many, the surreal proliferation of exotic devices would conjure the opening
scene of Dickens’s tale of yore: “It was the best of times, it was the worst of times,
it was the age of wisdom, it was the age of foolishness, it was the epoch of belief,
it was the epoch of incredulity, it was the season of Light, it was the season of
Darkness, it was the spring of hope, it was the winter of despair, we had everything
before us, we had nothing before. . . .”
The surreal proliferation of these exotic devices was an exciting time full of
opportunity and challenge. At this time, I was working on my PhD research to
make sense of the cornucopia of exotic nonlinear devices. Rather than charting a
taxonomy to pigeonhole them, I opted for an axiomatic definition of a few basic
nonlinear circuit elements that could be used to model a broad variety of nonlinear
devices. I joined the Purdue University upon graduation in 1964 and was assigned
to revamp its outdated circuit analysis curriculum, thereby providing me an ideal
launching pad for teaching nonlinear circuit theory through my device-independent
black-box approach. The axioms that would predict the memristor had made their
debut in the world’s first textbook on nonlinear circuit theory [23] in 1969. It
took a year for me to derive and prove mathematically the unique circuit-theoretic
properties and memory attributes of this yet unnamed device, earning its accolade
as the fourth circuit element [24, 25] and its justification for submission to the IEEE
Transactions on Circuit Theory on November 25, 1970 [4]. Its publication in the
following year coincided with my move to the University of California, Berkeley,
to spearhead research in a new frontier dubbed nonlinear circuits and systems. The
memristor was soon relegated to the back burner due to lack of research funding,
where, like Rip Van Winkle, it would slumber until awakened. This was despite
recognition by the IEEE of the potential of the memristor back in 1973, when they
awarded me the prestigious IEEE W.R.G. Baker Prize Paper Award for the most
outstanding paper reporting the original work in all IEEE publications.
To analyze circuits made of strongly nonlinear and dynamical electronic devices,
it is necessary to have realistic device models made of well-defined nonlinear
circuit elements as building blocks [23, 26], which did not exist then, because the
electrical engineers from that bygone epoch were taught to overcome nonlinearities
by expanding them in a Taylor series and then retaining only the linear term that
neatly maps into a linear circuit model. But just like the ancient parable about the
blind men and the elephant, such models invariably gave rise to grossly inaccurate
and misleading results. Unfortunately, the “linearize then analyze” culture endowed
upon the electronic engineers of the day had made it impossible to devise such
generalizations due in part to the lack of a circuit-theoretic foundation for basic
nonlinear circuit elements. Even Richard Feynman would sloppily use the old-
Preface
The dawn of nonlinear electronics was ushered during the 1960s by a Cambrianesque explosion of newly minted two-terminal electronic devices, bearing such
intimidating monikers as Esaki diode, Josephson junction, varactor diode, thyristor,
impact ionization avalanche transit time (IMPATT) diode, Gunn diode, and ovonic
threshold switch. Trained in the old school of linear circuit analysis, hordes of
electronics engineers were awed and shocked upon witnessing a parade of such
strongly nonlinear and dynamical electronic devices unfolding at such a breathless
rate. To many, the surreal proliferation of exotic devices would conjure the opening
scene of Dickens’s tale of yore: “It was the best of times, it was the worst of times,
it was the age of wisdom, it was the age of foolishness, it was the epoch of belief,
it was the epoch of incredulity, it was the season of Light, it was the season of
Darkness, it was the spring of hope, it was the winter of despair, we had everything
before us, we had nothing before. . . .”
The surreal proliferation of these exotic devices was an exciting time full of
opportunity and challenge. At this time, I was working on my PhD research to
make sense of the cornucopia of exotic nonlinear devices. Rather than charting a
taxonomy to pigeonhole them, I opted for an axiomatic definition of a few basic
nonlinear circuit elements that could be used to model a broad variety of nonlinear
devices. I joined the Purdue University upon graduation in 1964 and was assigned
to revamp its outdated circuit analysis curriculum, thereby providing me an ideal
launching pad for teaching nonlinear circuit theory through my device-independent
black-box approach. The axioms that would predict the memristor had made their
debut in the world’s first textbook on nonlinear circuit theory [23] in 1969. It
took a year for me to derive and prove mathematically the unique circuit-theoretic
properties and memory attributes of this yet unnamed device, earning its accolade
as the fourth circuit element [24, 25] and its justification for submission to the IEEE
Transactions on Circuit Theory on November 25, 1970 [4]. Its publication in the
following year coincided with my move to the University of California, Berkeley,
to spearhead research in a new frontier dubbed nonlinear circuits and systems. The
memristor was soon relegated to the back burner due to lack of research funding,
where, like Rip Van Winkle, it would slumber until awakened. This was despite
recognition by the IEEE of the potential of the memristor back in 1973, when they
awarded me the prestigious IEEE W.R.G. Baker Prize Paper Award for the most
outstanding paper reporting the original work in all IEEE publications.
To analyze circuits made of strongly nonlinear and dynamical electronic devices,
it is necessary to have realistic device models made of well-defined nonlinear
circuit elements as building blocks [23, 26], which did not exist then, because the
electrical engineers from that bygone epoch were taught to overcome nonlinearities
by expanding them in a Taylor series and then retaining only the linear term that
neatly maps into a linear circuit model. But just like the ancient parable about the
blind men and the elephant, such models invariably gave rise to grossly inaccurate
and misleading results. Unfortunately, the “linearize then analyze” culture endowed
upon the electronic engineers of the day had made it impossible to devise such
generalizations due in part to the lack of a circuit-theoretic foundation for basic
nonlinear circuit elements. Even Richard Feynman would sloppily use the old-