Todd Gaier

Dr. Todd Gaier is a Senior Research Scientist and the Supervisor for JPL’s Microwave Systems Technology Group as well as a Faculty Associate in Astronomy at Caltech. He is also a member of the Committee on Radio Frequencies of the National Academies of Science. He received his Ph.D in Physics from the University of California, Santa Barbara in 1993 studying the Cosmic Microwave Background (CMB). His research interests include millimeter wave electronics for applications in astrophysics and Earth remote sensing. His group develops technologies and instruments using monolithic microwave integrated circuit (MMIC) components operating at frequencies 1-250 GHz. Active projects in the group include the Planck-LFI mission to study the anisotropy and polarization of the CMB; the Q/U Imaging Experiment (QUIET) exploring the polarization of the CMB; GeoSTAR an interferometric synthetic aperture imager for Earth atmospheric sounding from geostationary orbit; the Advanced Microwave Radiometers for the Jason-II and III Missions mapping small variations in sea level across the globe monitoring conditions such as El-Nino and the integrated receivers for the Juno Microwave Radiometers.

  • 1986-1993, University of California, Santa Barbara, CA, degree awarded: Ph.D., Physics (6/93)
  • 1982-1985, Tufts University, Medford, MA, degree awarded: B.S.,Physics (12/85)

Research Interests: 

Dr. Gaier’s research interests span the range og microwave and millimeter wave device technology development, component development and test, integrated receiver systems and resulting Earth atmospheric and astrophysics science from these systems. He is the NASA Principal Investigator for the Q/U Imaging Experiment (QUIET), a co-Investigator and Scientist on Planck-LFI both studying the structure and polarization of the cosmic microwave background. He is co-Investigator on GeoSTAR technology development for the NASA Precipitation and All-weather Temperature and Humidity (PATH) mission. He is currently Principal Investigator of a JPL R&TD project to prototype a spectrometer array to map diffuse CO emission in the early universe.

Professional Experience: 
  • 2010-present Faculty Associate, Division of Physics, Math and Astronomy, California Institute of Technology,Pasadena, CA
  • 1996-Present, Senior Research Scientist and Group Supervisor, Jet Propulsion Laboratory, Pasadena, CA
    • Co-Investigator on SWOT ACT effort to develop compact water vapor radiometers for future remote sensing satellites.
    • Co-Investigator on NASA SARA (APRA) project to develop ultra-low-noise cryogenic amplifiers for astrophysics applications.
    • Co-Investigator /JPL PI on DARPA THz program to develop high power tube sources from 670-1050 GHz.
    • Co-Principal Investigator NASA IPP effort to develop ultra-low noise amplifiers from 40-150 GHz for Earth remote sensing and astrophysics applications.
    • Co-Investigator and JPL lead for DARPA SWIFT program developing 350 GHz amplifier technologies.
    • Principal Investigator for the Imaging Receiver Arrays effort under JPL’s R&TD program for remote sensing. Developing highly integrated, compact radiometers at 30-40 GHz.
    • JPL/NASA Principal Investigator, NSF Co-Investigator for Q/U Imaging ExperimenT (QUIET), imaging polarimetric array for mapping the polarization of the Cosmic Microwave Background. QUIET uses MMIC technology integrated into compact radiometers suitable for large focal plane array integration. Delivered more than 100 cryogenic radiometers for observations.
    • Co-Investigator and technical manager for GeoSTARI-III, NASA Earth Science Enterprise Instrument Incubator Programs, developing synthetic aperture radiometers at 60 and 183 GHz, for geostationary atmospheric sounding applications.
    • Planck-Low Frequency Instrument, Co-Investigator responsible for prototype development of 100 GHz ultra-low-noise cryogenic receivers for the ESA/NASA Planck satellite. Planck Scientist.
    • Principal Investigator for the Millimeter-wave Atmospheric Temperature and Humidity Sounder (MATHS), NASA Earth Science Instrument Incubator Program for mission enabling technologies. Developing broadband low noise heterodyne MMIC based receivers at 120 and 180 GHz. Receiver used in HAMSR experiment.
    • Principal Investigator for the Cryogenic HEMT Optimization Program (CHOP) which develops ultra-low noise InP transistor technologies for use in radiometers and telecommunications. This program has provided record low noise performance and has supplied the transistors and MMICs currently in use at FCRAO, CSO and MPIfR-Effelsberg telescopes. The program is also supporting the BEAST, CAPMAP, COMPASS and AMiBA CMB telescopes as well as the Planck and Herschel missions.
    • Collaborator and science team member of the CAPMAP CMB polarization experiment. Provided the low-noise amplifier front ends at 90 GHz.
    • Co-Investigator on the BEAST CMB mapping experiment.
    • Science team member of the AMiBA CMB Interferometer.
    • Pioneered the use of power amplifiers in THz local oscillator chains NASA’s development of power amplifier technologies from 70-115 GHz, for the Far Infrared and Submillimeter Telescope (FIRST) Heterodyne Instrument.
    • Founded and manage a millimeter-wave MMIC amplifier laboratory for testing and packaging of amplifiers and receiver systems up to 220 GHz.
    • Member of Earth Science and Technology Directorate Technology Advisory Council
    • Demonstrated amplifiers with record low 30 K noise at 100 GHz.
    • Demonstrated amplifiers with > 200 mW output power from 90-105 GHz.
    • Developed and demonstrated the world’s first use of wafer probe network analysis above 140 GHz.
    • Co-developed and tested the world’s first MMIC amplifiers above 140 GHz.
    • Demonstrated the world’s highest frequency amplifier (215 GHz and 350 GHz).
    • Invented a bandpass filter tunable from 78-105 GHz.
    • Invented and demonstrated the use of amplifiers as millimeter noise sources.
  • 1996 Physicist, Spacek Labs Inc., Santa Barbara, CA
    • Directed development of a successful MMIC based amplifier product line.
    • Design and test of packaging schemes for MMIC amplifiers
  • 1993-1996, Post-Doctoral Researcher, Physics Dept., University of California, Santa Barbara, CA.
    • Design and fabrication of ultra-low noise cryogenic microwave/millimeter wave receivers and test systems.
    • Collaborated with TRW in building and testing a cryogenic 94 GHz InP MMIC amplifier. The unit had a measured a record noise figure of 51 K.
    • Design, development and test of low noise cryogenic HEMT amplifiers from 12-90 GHz, using GaAs and InP technologies. Co-developed cryogenic amplifiers at 43 GHz with 10 K noise and 30 GHz with 9 K noise.
    • Developed new techniques for receiver stabilization. Designed, built and tested a cryogenic oscillator stabilized receiver.
    • Designed and developed a technique for characterizing the DC stability of RF detector diodes. Successfully tested and characterized several commercial detector diodes.
    • Member of a JPL/TRW/UCSB/Georgia Tech collaboration to develop InP HEMT transistors for cryogenic low noise millimeter wave applications.
    • Planned and organized the 1995 UCSB Workshop on Low Noise Microwave and Millimeter- Wave Amplifiers. The workshop was attended by 50 participants from universities, industry and government research laboratories.
    • Senior member of team carrying out an experiment to measure CMB anisotropy from Antarctica, resulting in extensively cited publications.
  • 1988-1993, Research Assistant, Physics Dept., University of California, Santa Barbara, CA
    • Designed an experiment to measure CMB anisotropy at 1o. Responsible for the development of the cryogenic receivers (25-35 GHz) and optical elements of this experiment. Responsible for the successful running of the experiment at the South Pole during the 1990-91 austral summer and subsequent data analysis and broadly cited publication (1990-1993).
    • Designed and fabricated an experiment to measure CMB anisotropy at 10o. The telescope was designed for extended ground based observations from Antarctica and White Mt., CA. The receivers operated at 15 and 23 GHz and employed a closed cycle He refrigerator permitting extended low noise operation. Responsible for all aspects of the experiment including its design construction and successful operation in 1988-1989
    • Constructed 15 GHz cryogenic HEMT amplifiers with 15 K noise figure (1987).
    • Assisted in a balloon borne experiment to measure the spectrum of the CMB at 90 GHz.
    • Constructed cryogenic low noise HEMT amplifiers at 1.8 GHz for the IF portion of a 90 GHz SIS receiver used to map CMB fluctuations at 0.5o. The amplifers had a noise figure near 1 K (1987).
    • Provided direction and assistance to undergraduate students working on these projects
  • 1986-1987, Teaching Assistant, Physics Dept., University of California, Santa Barbara, CA
    • Teaching Assistant for upper division undergraduate astrophysics course.
    • Lab instructor for a variety of undergraduate classes.
    • Instructed help sections for undergraduate students.
  • 1984-1985, Research Assistant , Physics Dept. Tufts University, Medford MA
    • Worked in the high energy physics group analyzing data and developing electronics.
    • Participated in a bubble chamber neutrino experiment on site at Fermilab

Selected Awards: 
  • 2010, NASA Group Achievement Award, Planck-LFI
  • 2008-2010 Multiple NASA Tech Brief Awards
  • 2003, NASA Space Act Award
  • 2002, JPL Group Award
  • 2000-2008, NASA Tech Brief Awards (>10)
  • 1999, JPL Award of Excellence
  • 1998, 10th Anniversary Paper Award, Indium Phosphide and Related Materials Conference
  • 1989, University of California White Mountain Research Station Research Fellowship
  • 1984-85 and 1985-86, N. Hobbs Knight Award Fellowship in Physics, Tufts University

Selected Publications: 
  1. “Second Season QUIET Observations: Measurements of the CMB Polarization Power Spectrum at 95 GHz” QUIET Collaboration — D. Araujo, C. Bischoff, A. Brizius, I. Buder, Y. Chinone, K. Cleary, R. N. Dumoulin, A. Kusaka,, R. Monsalve, S. K. Næss, L. B. Newburgh, R. Reeves, I. K. Wehus, J. T. L. Zwart, L. Bronfman, R. Bustos, S. E. Church, C. Dickinson, H. K. Eriksen, T. Gaier, J. O. Gundersen, M. Hasegawa, M. Hazumi, K. M. Huffenberger, K. Ishidoshiro, M. E. Jones, P. Kangaslahti, D. J. Kapner, D. Kubik, C. R. Lawrence, M. Limon, J. J. McMahon, A. D. Miller, M. Nagai, H. Nguyen, G. Nixon, T. J. Pearson, L. Piccirillo, S. J. E. Radford, A. C. S. Readhead, J. L. Richards, D. Samtleben, M. Seiffert, M. C. Shepherd, K. M. Smith, S. T. Staggs, O. Tajima, K. L. Thompson, K. Vanderlinde, R. Williamson, accepted ApJ 2012.
  2. “First Season QUIET Observations: Measurements of CMB Polarization Power Spectra at 43 GHz in the Multipole Range 25 <= ell <= 475” QUIET Collaboration Bischoff, C.; Brizius, A.; Buder, I.; Chinone, Y.; Cleary, K.; Dumoulin, R. N.; Kusaka, A.; Monsalve, R.; Næss, S. K.; Newburgh, L. B.; Reeves, R.; Smith, K. M.; Wehus, I. K.; Zuntz, J. A.; Zwart, J. T. L.; Bronfman, L.; Bustos, R.; Church, S. E.; Dickinson, C.; Eriksen, H. K.; Ferreira, P. G.; Gaier, T.; Gundersen, J. O.; Hasegawa, M.; Hazumi, M.; Huffenberger, K. M.; Jones, M. E.; Kangaslahti, P.; Kapner, D. J.; Lawrence, C. R.; Limon, M.; May, J.; McMahon, J. J.; Miller, A. D.; Nguyen, H.; Nixon, G. W.; Pearson, T. J.; Piccirillo, L.; Radford, S. J. E.; Readhead, A. C. S.; Richards, J. L.; Samtleben, D.; Seiffert, M.; Shepherd, M. C.; Staggs, S. T.; Tajima, O.; Thompson, K. L.; Vanderlinde, K.; Williamson, R.; Winstein, B. ApJ, 741, 111 2011.
  3. “First Measurements of the Polarization of the Cosmic Microwave Background Radiation at Small Angular Scales from CAPMAP” , Barkats, D.; Bischoff, C.; Farese, P.; Fitzpatrick, L.; Gaier, T.; Gundersen, J. O.; Hedman, M. M.; Hyatt, L.; McMahon, J. J.; Samtleben, D.; Staggs, S. T.; Vanderlinde, K.; Winstein, B., et al, Astrophysical Journal Lett, Vol 619, L127, 2005.
  4. “Measurement of a 270 GHz Low Noise Amplifier With 7.5 dB Noise Figure”, Gaier, T., Samoska, L., Fung, A., Deal, W.R., Radisic, V., Mei, X.B., Yoshida, W., Liu, P.H., Uyeda, J., Barsky, M., Lai, R., Microwave and Wireless Components Letters, IEEE, Volume 17, Issue 7, July 2007 Pp.546 - 548.
  5. “W-band InP wideband MMIC LNA with 30 K noise temperature”, Weinreb, S., Lai, R., Erickson, N., Gaier, T., Wielgus, J. Microwave Symposium Digest, 1999 IEEE MTT-S International , Volume: 1 , 1999, Pp.101 -104 vol.1.
  6. “Cryogenic measurements of 183 GHz MMIC low noise amplifiers”, Dawson, D.; Gaier, T.; Raja, R.; Nishimoto, M.; Lai, R.; Wells, M.; Microwave Symposium Digest, 2003 IEEE MTT-S International ,Volume: 3 , 8-13 June 2003 Pages:1585 - 1587 vol.3.

Additional Publications


  1. “Planck pre-launch status: Calibration of the Low Frequency Instrument flight model radiometers”, Villa, F.; Terenzi, L.; Sandri, M.; Meinhold, P.; Poutanen, T.; Battaglia, P.; Franceschet, C.; Hughes, N.; Laaninen, M.; Lapolla, P.; Bersanelli, M.; Butler, R. C.; Cuttaia, F.; D'Arcangelo, O.; Frailis, M.; Franceschi, E.; Galeotta, S.; Gregorio, A.; Leonardi, R.; Lowe, S. R.; Mandolesi, N.; Maris, M.; Mendes, L.; Mennella, A.; Morgante, G.; Stringhetti, L.; Tomasi, M.; Valenziano, L.; Zacchei, A.; Zonca, A.; Aja, B.; Artal, E.; Balasini, M.; Bernardino, T.; Blackhurst, E.; Boschini, L.; Cappellini, B.; Cavaliere, F.; Colin, A.; Colombo, F.; Davis, R. J.; de La Fuente, L.; Edgeley, J.; Gaier, T.; Galtress, A.; Hoyland, R.; Jukkala, P.; Kettle, D.; Kilpia, V.-H.; Lawrence, C. R.; Lawson, D.; Leahy, J. P.; Leutenegger, P.; Levin, S.; Maino, D.; Malaspina, M.; Mediavilla, A.; Miccolis, M.; Pagan, L.; Pascual, J. P.; Pasian, F.; Pecora, M.; Pospieszalski, M.; Roddis, N.; Salmon, M. J.; Seiffert, M.; Silvestri, R.; Simonetto, A.; Sjoman, P.; Sozzi, C.; Tuovinen, J.; Varis, J.; Wilkinson, A.; Winder, F., Astronomy and Astrophysics, Volume 520, id.A6, 2010.
  2. “Coherent detectors”, Lawrence, C. R.;,Church, S., Gaier, T., Lai, R., Ruf, C., Wollack, E., Journal of Physics: Conference Series, Volume 155, Issue 1, pp. 012002 (2009).
  3. “A Map of the Cosmic Microwave Background from the BEAST Experiment”, Meinhold, Peter R.; Bersanelli, Marco; Childers, Jeffrey; Figueiredo, Newton; Gaier, Todd C.; Halevi, Doron; Huey, Gregory G.; Kangas, Miikka; Lawrence, Charles R.; Levy, Alan; Lubin, Philip M.; Malaspina, Marco; Mandolesi, Nazzareno; Marvil, Joshua; Mejía, Jorge; Natoli, Paolo; O'Dwyer, Ian; O'Neill, Hugh; Parendo, Shane; Pina, Agenor; Seiffert, Michael D.; Stebor, Nathan C.; Tello, Camilo; Villa, Fabrizio; Villela, Thyrso; Wade, Lawrence A.; Wandelt, Benjamin D.; Williams, Brian; Wuensche, Carlos AlexandreAp J Supp., Volume 158, Issue 1, pp. 101-108 2005.
  4. ”Amplifier arrays for CMB polarization” Gaier, Todd, Lawrence, Charles R., Seiffert, Michael D., Wells, Mary M., Kangaslahti, Pekka, Dawson, Douglas , New Astronomy Reviews, Volume 47, Issue 11-12, p. 1167-1171, 2003.
  5. “A degree-scale measurement of anisotropy of the cosmic background radiation” Gaier, Todd, Schuster, Jeffrey Gundersen, Joshua, Koch, Timothy, Seiffert, Michael, Meinhold, Peter, Lubin, Philip, Astrophysical Journal, Part 2 - Letters , vol. 398, no. 1, p. L1-L4., 1992.


Todd Gaier
4800 Oak Grove Dr.
Pasadena, CA 91109
Phone: 818.354.4402
Fax Number: 818.393.4683