Ali Hajimiri

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Ali Hajimiri
ResidenceUnited States
NationalityIranian American
Alma materSharif University of Technology (B.S.)
Stanford University (M.S., Ph.D.)
AwardsFeynman Prize for Excellence in Teaching (2019);Microwave Prize (2015);
Excellence in Teaching Award: Associated Students of California Institute of Technology (2004 and 2014);
Teaching and Mentorship Award: Graduate Student Council, California Institute of Technology (2005);
MIT Technology Review Magazine TR35 Top Young Innovators (2004);
IBM Faculty Partnership Award (2003);
NSF Career Award (2002);
Bronze Medal, 21st International Physics Olympiad (1990);
Gold Medal (absolute winner), National Physics Olympiad (1990).
Scientific career
FieldsElectrical Engineering
InstitutionsCalifornia Institute of Technology
Doctoral advisorThomas H. Lee
Bruce A. Wooley

Ali Hajimiri is an academic, inventor, and entrepreneur in various fields of technology including electrical engineering and biomedical engineering. He is currently the Bren Professor of Electrical Engineering and Medical Engineering at the California Institute of Technology (Caltech).

He received the B.S. degree in electrical engineering from Sharif University of Technology and his M.S. and Ph.D. degrees in electrical engineering from Stanford University. He has also worked for Bell Laboratories, Philips Semiconductors, and Sun Microsystems. As a part of his Ph.D. thesis, he developed a time-varying phase noise model for electrical oscillators,[1] also known as the Hajimiri phase noise model.[2] In 2002, he cofounded Axiom Microdevices Inc. together with his former students Ichiro Aoki and Scott Kee based on their invention of the Distributed Active Transformer (DAT), which made it possible to integrate RF CMOS power amplifiers suitable for cellular phones in CMOS technology. Axiom shipped hundreds of millions of units before it was acquired by Skyworks Solutions in 2009.

He and his students also demonstrated the world's first radar-on-a-chip in silicon technology in 2004,[3] showing a pair of 24 GHz 8-element phased array receiver,[4] and a 4-element phased array transmitter in CMOS.[5] These were followed by a 77 GHz phased array transceiver (transmitter and receiver) with on chip antennas that established the highest level of integration in mm-wave frequency applications and was a complete radar-on-a-chip.[6][7] They also developed a fully scalable phased array architecture, making it possible to make very large scale phased arrays possible in 2008.[8]

He and his team are also responsible for the development of an all-silicon THz imager system, where an integrated CMOS microchip was used in conjunction with a second silicon microchip to form an active THz imaging system, capable of seeing through opaque objects. They demonstrated various phased array transmitters around 0.3THz with beam steering using the distributed active radiator (DAR) architecture in 2011.[9] Various applications of this system appear in security, communications, medical diagnostics, and the human-machine interface.[10][11][12]

In 2013, he and some of his team members demonstrated a complete self-healing power amplifier, which through an integrated self-healing strategy, could recover from various kinds of degradation and damage including aging, local failure, and intentional laser blasts.[13][14][15][16]

Between 2014 and 2017, he and his team demonstrated three major advances in imaging and projection technology using silicon photonics platforms.[17][18][19] In 2014, they showed the first silicon-nanophotonics optical phased array transmitter capable of dynamic and real-time image projection, which serves as a lensless projector.[20][21] In 2015, he and his team demonstrated a 3D coherent camera, using a silicon nano-photonics coherent imager (NCI) platform that demonstrated direct 3D imaging at meter range with 15-micron depth resolution.[22][23] In 2016, they devised and implemented a one-dimensional (1D) integrated optical phased array receiver demonstrating the first lensless flat camera for the first time, imaging a bar coding directly from the surface of a chip.[24] In 2017, he and his team demonstrated the first integrated two-dimensional (2D) optical phased array receiver, imaging simple 2D patterns without a lens with a very thin optical synthetic aperture of a few microns, demonstrating the first lensless flat camera.[25][26]

He is a Fellow of National Academy of Inventors (NAI).[27] He was selected to the world's top 35 innovators under 35 (TR35) at age 32.[28] He is an IEEE Fellow and has been the recipient of numerous other awards.[29] He was recognized as one of the top 10 authors in the 60-year history of ISSCC in 2013. He holds more than 100 granted U.S. patents.[30] He was one of 45 scientists invited to speak at the World Economic Forum in 2016.[31] As of 2016, over half of his graduated PhD students have gone on to become university faculty members.[32]

Hajimiri has also won numerous prizes as an educator, such as Feynman Prize for excellence in teaching, which is Caltech’s most prestigious teaching award,[33], as well as the awards from undergraduate and graduate student councils.[34] His online lectures on youtube are a popular source of continued education worldwide.[35]

His favorite band is Pink Floyd.


  • The Design of Low Noise Oscillators, co-authored with Thomas H. Lee, Springer, 1999, ISBN 0-7923-8455-5


  1. ^ A General Theory of Phase Noise in Electrical Oscillators. (PDF), IEEE, February 1998
  2. ^ The Design of CMOS Radio-Frequency Integrated Circuits, First Edition. Cambridge University Press. 1998.
  3. ^ "Caltech Engineers Design a Revolutionary Radar Chip" (Press release). Caltech Media Relations. May 4, 2004. Archived from the original on 2010-05-31. Retrieved 2010-11-19.
  4. ^ "A Fully Integrated 24GHz 8-Path Phased-Array Receiver in Silicon" (PDF). Archived from the original (PDF) on 2015-09-09.
  5. ^ "A 24GHz Phased-Array Transmitter in 0.18μm CMOS" (PDF). Archived from the original (PDF) on 2015-09-09.
  6. ^ "A 77GHz 4-Element Phased Array Receiver with On-Chip Dipole Antennas in Silicon" (PDF). Archived from the original (PDF) on 2015-09-10.
  7. ^ "A 77GHz Phased-Array Transmitter with Local LO- Path Phase-Shifting in Silicon" (PDF). Archived from the original (PDF) on 2015-09-09.
  8. ^ "A Scalable 6-to-18 GHz Concurrent Dual-Band Quad-Beam Phased-Array Receiver in CMOS" (PDF). Archived from the original (PDF) on 2015-09-06.
  9. ^ "A 0.28THz 4×4 Power-Generation and Beam-Steering Array" (PDF). Archived from the original (PDF) on 2015-09-06.
  10. ^ "Ali Hajimiri's Chip May Allow Smartphones to See Through Objects".
  11. ^ "Give your smartphone Superman vision". Fox News. December 19, 2012.
  12. ^ "A New Tool for Secret Agents—And the Rest of Us".
  13. ^ "How Self-Healing Microchips Recover".
  14. ^ "Self-healing chip survives laser blast".
  15. ^ "Microchip Adapts to Severe Damage".
  16. ^ "Self-healing chips survive repeated LASER BLASTS".
  17. ^ "Laser-Bending Chip Could Put A Projector in Your Pocket".
  18. ^ "Nanophotonic coherent imager".
  19. ^ "Laser Chip Could Turn Smartphones Into Handheld 3D Scanners".
  20. ^ "Bending the Light with a Tiny Chip".
  21. ^ "Electronic two-dimensional beam steering for integrated optical phased arrays" (PDF).
  22. ^ "New Camera Chip Provides Superfine 3-D Resolution".
  23. ^ "Nanophotonic coherent imager" (PDF).
  24. ^ "A One-Dimensional Heterodyne Lens-Free OPA Camera".
  25. ^ "Ultra-Thin Camera Creates Images Without Lenses".
  26. ^ "An 8x8 Heterodyne Lens-less OPA Camera".
  27. ^ "National Academy of Inventors". Retrieved 2017-07-05.
  28. ^ "TR35: Ali Hajimiri, 32, Technology Review".
  29. ^ "Ali Hajimiri's Biography, Caltech".
  30. ^ "US Patent Office".
  31. ^ "Scientists at the World Economic Forum 2016".
  32. ^ "Ali Hajimiri's Academic Genealogy, Caltech".
  33. ^ "Ali Hajimiri Awarded 2019 Feynman Teaching Prize".
  34. ^ "ASCIT teaching awards".
  35. ^ "Hajimiri online lectures".

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