2013 McCoy Award Recipient
Scifres Family Distinguished Professor of Electrical and Computer Engineering
Andrew Weiner is the Scifres Family Distinguished Professor of Electrical and Computer Engineering. In 2008 he was elected to membership in the National Academy of Engineering, and in 2009 he was named a Department of Defense National Security Science and Engineering Faculty Fellow.
Weiner recently served a three-year term as Chair of the National Academy’s U.S. Frontiers of Engineering meeting. At present, he serves as editor-in-chief of Optics Express, an all-electronic, open-access journal publishing more than 3,000 papers a year emphasizing innovations in all aspects of optics and photonics.
After Weiner earned his ScD in electrical engineering in 1984 from the Massachusetts Institute of Technology, he joined Bellcore, at that time a premier telecommunications industry research organization, first as a member of technical staff and later as manager of Ultrafast Optics and Optical Signal Processing Research. He joined Purdue as a professor in 1992 and has since graduated 30 PhD students.
Professor Weiner’s research focuses on ultrafast optics, with an emphasis on processing of extremely high-speed lightwave signals. He is known for his advancements in the programmable generation of arbitrary ultrashort pulse waveforms, which has found application both in fiber optic networks and in ultrafast optical science laboratories around the world.
He is the author of a textbook entitled Ultrafast Optics, has published eight book chapters and more than 270 journal articles. Weiner holds 15 U.S. patents. His numerous awards include the Hertz Foundation Doctoral Thesis Prize (1984), the Optical Society of America’s Adolph Lomb Medal (1990) and R.W. Wood Prize (2008), the International Commission on Optics Prize (1997), and the IEEE Photonics Society’s William Streifer Scientific Achievement Award (1999) and Quantum Electronics Prize (2011).
At Purdue, he has been recognized with the inaugural Research Excellence Award from the Schools of Engineering (2003) and with the Provost’s Outstanding Graduate Student Mentor Award (2008).
Lasers capable of generating picosecond and femtosecond pulses of light are now firmly established and are widely deployed. Professor Weiner’s pioneering work on programmable shaping of ultrafast laser fields into arbitrary waveforms has resulted in substantial impact, both enabling new ultrafast science and influencing practical applications in transmission of high-speed lightwave and wireless signals. The lecture begins with a brief introduction to ultrafast optics and then specifically addresses methods permitting shaping of ultrafast laser fields on time scales too fast for direct electronic control. Several examples illustrating a new area of science — in which researchers worldwide use shaped laser pulses as tools to manipulate nanoscopic and quantum mechanical processes, including simple photochemical reactions — will be described. The final section of the lecture focuses on recent work from the Weiner Laboratory in which pulse shaping and related photonic processing tools are applied to enhance transmission both of lightwave signals over fiber optic cables and of wireless signals in highly scattering indoor propagation environments.
Professor Andrew Weiner is widely known for his seminal contributions to the science of ultrashort optical pulse generation with arbitrary waveforms and for the applications of this science in a number of different technologies.
The impact of his work has been significant. Pulse shaping is now employed in ultrafast optics laboratories around the world, enabling research in fields as diverse as coherent quantum control, single cycle optical pulse generation, nonlinear optical microscopy and imaging, high-speed lightwave communications, and ultrabroadband radio-frequency photonics.
Weiner’s contributions include the first demonstration of femtosecond time scale pulse shaping (1988, joint with J.P. Heritage) and invention of the first programmable pulse shaping methods (1990-92). The development of programmable pulse shaping technology, using liquid crystal spatial light modulators patented and first demonstrated by Weiner, was a key step that enabled the widespread adoption of this technique. Weiner’s pioneering work spurred others to explore new applications and to develop new types of spatial light modulators suitable for use in pulse shaping systems.
The ability to program pulse shapes enabled new classes of adaptive pulse shaping systems, in which waveforms selected for optimum experimental results are obtained automatically via iterative computer learning algorithms. The basic optical layout demonstrated and popularized by Weiner has been adapted to realize commercial products, ranging from high-intensity femtosecond amplifiers used for a broad spectrum of research in ultrafast optical science to modules used in the optical communications industry.
Weiner also is known for a series of elegant, groundbreaking experiments demonstrating the potential of optical pulse shaping to open up areas in science and new applications in technology. His 1990 Science paper on application of femtosecond pulse sequences for selective amplification of optical phonons in molecular crystals is one of the earliest examples of the now very active field of coherent and quantum control, in which specially controlled ultrafast laser waveforms are used to manipulate light-matter interactions. Examples of experiments in this field include selective enhancement of high harmonic radiation from atoms driven by strong laser fields, laser controlled chemistry, spatially selective excitation of plasmons in metallic nanostructures and spectrally (hence chemically) selective microscopy.
Weiner conceived a spectral phase equalizer principle for programmable compensation of pulse spreading and distortion due to frequency-dependent delay phenomena, which is now frequently used for applications ranging from short pulse transmission in optical fibers to compression of pulses in high power amplifier systems, at the foci of microscopes and to durations approaching the single cycle limit. Femtosecond pulse shaping is a key enabler for all of this work.
In recent years, Professor Weiner has continued to exploit ideas and technologies originating from the fields of ultrafast optics and pulse shaping to develop new concepts for manipulation and processing of ultrahigh-speed signals. Through this work, he has opened up three exciting new lines of research, as summarized briefly below.
LINE-BY-LINE PULSE SHAPING
The new field of femtosecond frequency combs, recognized with the 2005 Nobel Prize in Physics for its revolutionary impact on optical frequency metrology, fundamentally deals with optical spectra at the individual spectral line level. Through his work for the first time applying pulse shaping to the individual lines of a frequency comb, new opportunities now exist in areas ranging from high-resolution nonlinear spectroscopy to secure communications.
ULTRABROADBAND RADIO-FREQUENCY PHOTONICS
Radio-frequency (RF) systems are ubiquitous in applications ranging from radar to wireless communications. Conventional RF systems are designed from a frequency domain perspective, with signals operating at low instantaneous bandwidth and well-defined center frequency. Femtosecond optics, on the other hand, is fundamentally time-domain in nature, and complex waveform control (thanks, for example, to pulse shaping) is now common. The Weiner group has performed groundbreaking experiments demonstrating that ultrafast photonics approaches, including pulse shaping, can be exploited for generating and processing user-defined ultrabroadband RF electrical signals with tens of GHz instantaneous bandwidths (in some cases approaching 1 THz), far outstripping purely electronic approaches and opening completely new possibilities.
NOVEL SIGNAL PROCESSING WITH MICRO-RESONATORS
Weiner, working with Professor M. Qi, conceived and demonstrated pulse shaping chips to achieve arbitrary RF waveform generation and demonstrated a new scheme, based on asymmetrically coupled nonlinear resonators, for one-way transmission of light, resulting in optical diode action with nearly three order of magnitude contrast between forward and reverse propagation. Further work on nonlinear micro-resonator chips produced sub-picosecond pulses at rates as high as hundreds of GHz, as well as first delineation of coherent (low noise), and partially coherent (noisy) modes of operation. Control of coherence and noise of micro-resonator-generated combs has since emerged as a major topic in this rapidly growing field.