Dr. Jagadishwar Sirigiri

Jagadishwar Sirigiri, is a founder of Bridge12 Technologies, Inc. and serves as its President and Chief Operating Officer. He has a M.S. and Ph.D. in Electrical Engineering and Computer Science from the Massachusetts Institute of Technology, Cambridge, MA. Dr. Sirigiri has over three decades of experience in experimental and theoretical aspects of microwave engineering, vacuum electron devices and terahertz technology. Previously, he was a Research Scientist at MIT where he was the leader of the experimental program on high power microwave and terahertz source development including gyrotrons and other types of sources for application in DNP-NMR spectroscopy, Electron Paramagnetic Resonance (EPR), fusion plasma heating and radar. He has conducted theoretical and experimental research on Photonic Band Gap (PBG) structures and Metamaterials (MTM).

Dr. Sirigiri’s research resulted in several accomplishments including the experimental demonstration of > 50% efficiency in a megawatt class gyrotron for plasma heating application; theoretical and experimental research on After Cavity Interaction (ACI) in gyrotrons and its effect on efficiency; theoretical and experimental work on the low frequency oscillations in megawatt gyrotron oscillators; development of tunable continuous wave gyrotron oscillators in the millimeter wave and terahertz range and their successful application in high field DNP-NMR  spectroscopy; development of high power high frequency gyrotron traveling wave tube (gyro-TWT) amplifiers at 140 GHz for applications in radar and electron EPR. He demonstrated the first vacuum electron device with a photonic band gap (PBG) structure to suppress mode competition while operating in a higher order mode. This concept is particularly useful for design of terahertz vacuum electron devices. He initiated work on the development of a 94 GHz traveling wave tube (TWT) with an overmoded interaction structure and a 250 GHz gyro-TWT amplifier using a higher order mode in a photonic band gap (PBG) structure.

Dr. Sirigiri is a Senior Member of the IEEE, and a member of the American Physical Society and Sigma-Xi. He served as a guest editor of the Twelfth Special Issue on High Power Microwave Generation of the IEEE Transactions on Plasma Sciences in 2008. He is a member of the IEEE Electron Devices Society (EDS) Vacuum Electron Devices Technical committee and member of the executive committee of the International Vacuum Electronics Conference (IVEC) He was the Technical Program Chair of IVEC in 2018 and the General Chair in 2020.

Publications (Selected)

For a complete publication list please please visit Google Scholar or PubMed or Orcid.

  1. Park, Dongkeun, Junseong Kim, Philip C. Michael, and Jagadishwar R. Sirigiri. “Conceptual Design of 15 T/220 mm Magnet for 350 GHz, 1 MW Gyrotrons for Fusion Reactors.” IEEE Transactions on Applied Superconductivity (2023). https://doi.org/10.1109/TASC.2023.3344546

  2. Liu, Xianzi, Calvin W. Domier, J. Dannenberg, Yilun Zhu, J. R. Sirigiri, Yang Ren, B. Stratton, and N. C. Luhmann. “The National Spherical Torus Experiment-Upgrade poloidal high-k scattering system pitch angle design modifications.” Review of Scientific Instruments 93, no. 10 (2022). https://doi.org/10.1063/5.0099912

  3. Domier, C. W., J. Dannenberg, Y. Zhu, X. Liu, J. R. Sirigiri, Y. Ren, B. Stratton, and N. C. Luhmann. “A poloidal high-k scattering system for NSTX-U.” Journal of Instrumentation 17, no. 01 (2022): C01018. https://doi.org/10.1088/1748-0221/17/01/C01018

  4. Han, Seong-Tae, Jagadishwar R. Sirigiri, Hasina Khatun, Varun Pathania, and Jongsoo Kim. “Development of a compact W-band gyrotron system with a depressed collector.” IEEE Transactions on Plasma Science 49, no. 2 (2021): 672-679. https://doi.org/10.1109/TPS.2021.3050748

  5. Keller, Timothy J., Alexander J. Laut, Jagadishwar Sirigiri, and Thorsten Maly. “High-resolution Overhauser dynamic nuclear polarization enhanced proton NMR spectroscopy at low magnetic fields.” Journal of Magnetic Resonance 313 (2020): 106719. https://doi.org/10.1016/j.jmr.2020.106719

  6. Lin, Li, Zichao Hou, Xiaoliang Yao, Yi Liu, Jagadishwar R. Sirigiri, Taeyoung Lee, and Michael Keidar. “Introducing adaptive cold atmospheric plasma: The perspective of adaptive cold plasma cancer treatments based on real-time electrochemical impedance spectroscopy.” Physics of Plasmas 27, no. 6 (2020). https://doi.org/10.1063/5.0003528

  7. Han, Seong-Tae, Antonio C. Torrezan, Jagadishwar R. Sirigiri, Michael A. Shapiro, and Richard J. Temkin. “Real-time, T-ray imaging using a sub-terahertz gyrotron.” Journal of the Korean Physical Society 60 (2012): 1857-1861. https://doi.org/10.3938/jkps.60.1857

  8. Maly, Thorsten, and Jagadishwar R. Sirigiri. “Simplified THz instrumentation for high-field DNP-NMR spectroscopy.” Applied magnetic resonance 43 (2012): 181-194. https://doi.org/10.1007/s00723-012-0360-7

  9. Torrezan, Antonio C., Michael A. Shapiro, Jagadishwar R. Sirigiri, Richard J. Temkin, and Robert G. Griffin. “Operation of a continuously frequency-tunable second-harmonic CW 330-GHz gyrotron for dynamic nuclear polarization.” IEEE Transactions on Electron Devices 58, no. 8 (2011): 2777-2783. https://doi.org/10.1109/TED.2011.2148721

  10. Tax, David S., Eunmi M. Choi, Ivan Mastovsky, Jeffrey M. Neilson, Michael A. Shapiro, Jagadishwar R. Sirigiri, Richard J. Temkin, and Antonio C. Torrezan. “Experimental results on a 1.5 MW, 110 GHz gyrotron with a smooth mirror mode converter.” Journal of Infrared, Millimeter, and Terahertz Waves 32 (2011): 358-370. https://doi.org/10.1007/s10762-010-9720-2

  11. Kim, H. J., E. A. Nanni, M. A. Shapiro, J. R. Sirigiri, P. P. Woskov, and R. J. Temkin. “Amplification of picosecond pulses in a 140-GHz gyrotron-traveling wave tube.” Physical review letters 105, no. 13 (2010): 135101. https://doi.org/10.1103/PhysRevLett.105.135101

  12. Kowalski, Elizabeth J., David S. Tax, Michael A. Shapiro, Jagadishwar R. Sirigiri, Richard J. Temkin, Timothy S. Bigelow, and David A. Rasmussen. “Linearly polarized modes of a corrugated metallic waveguide.” IEEE Transactions on microwave theory and techniques 58, no. 11 (2010): 2772-2780. https://doi.org/10.1109/TMTT.2010.2078972

  13. Barnes, Alexander B., Björn Corzilius, Melody L. Mak-Jurkauskas, Loren B. Andreas, Vikram S. Bajaj, Yoh Matsuki, Marina L. Belenky et al. “Resolution and polarization distribution in cryogenic DNP/MAS experiments.” Physical Chemistry Chemical Physics 12, no. 22 (2010): 5861-5867. https://doi.org/10.1039/C003763J

  14. Torrezan, Antonio C., Seong-Tae Han, Ivan Mastovsky, Michael A. Shapiro, Jagadishwar R. Sirigiri, Richard J. Temkin, Alexander B. Barnes, and Robert G. Griffin. “Continuous-wave operation of a frequency-tunable 460-GHz second-harmonic gyrotron for enhanced nuclear magnetic resonance.” IEEE Transactions on Plasma Science 38, no. 6 (2010): 1150-1159. https://doi.org/10.1109/TPS.2010.2046617

  15. Barnes, Alexander B., Melody L. Mak-Jurkauskas, Yoh Matsuki, Vikram S. Bajaj, Patrick CA van der Wel, Ronald DeRocher, Jeffrey Bryant et al. “Cryogenic sample exchange NMR probe for magic angle spinning dynamic nuclear polarization.” Journal of Magnetic Resonance 198, no. 2 (2009): 261-270. https://doi.org/10.1016/j.jmr.2009.03.003

  16. Joye, Colin D., Michael A. Shapiro, Jagadishwar R. Sirigiri, and Richard J. Temkin. “Demonstration of a 140-GHz 1-kW confocal gyro-traveling-wave amplifier.” IEEE Transactions on electron devices 56, no. 5 (2009): 818-827. https://doi.org/10.1109/TED.2009.2015802

  17. Barnes, A. B., G. De Paëpe, P. C. A. Van Der Wel, K-N. Hu, C-G. Joo, V. S. Bajaj, M. L. Mak-Jurkauskas et al. “High-field dynamic nuclear polarization for solid and solution biological NMR.” Applied magnetic resonance 34 (2008): 237-263. https://doi.org/10.1007/s00723-008-0129-1

  18. Maly, Thorsten, Galia T. Debelouchina, Vikram S. Bajaj, Kan-Nian Hu, Chan-Gyu Joo, Melody L. Mak–Jurkauskas, Jagadishwar R. Sirigiri et al. “Dynamic nuclear polarization at high magnetic fields.” The Journal of chemical physics 128, no. 5 (2008). https://doi.org/10.1063/1.2833582

  19. Hidaka, Yoshiteru, EunMi Choi, I. Mastovsky, M. A. Shapiro, J. R. Sirigiri, and R. J. Temkin. “Observation of Large Arrays of Plasma Filaments in Air Breakdown by 1.5-MW 110-GHz Gyrotron Pulses.” Physical review letters 100, no. 3 (2008): 035003. https://doi.org/10.1103/PhysRevLett.100.035003

  20. Bajaj, Vikram S., Melissa K. Hornstein, Kenneth E. Kreischer, Jagadishwar R. Sirigiri, Paul P. Woskov, Melody L. Mak-Jurkauskas, Judith Herzfeld, Richard J. Temkin, and Robert G. Griffin. “250 GHz CW gyrotron oscillator for dynamic nuclear polarization in biological solid state NMR.” Journal of Magnetic Resonance 189, no. 2 (2007): 251-279. https://doi.org/10.1016/j.jmr.2007.09.013

  21. Choi, EunMi, M. A. Shapiro, J. R. Sirigiri, and R. J. Temkin. “Experimental observation of the effect of aftercavity interaction in a depressed collector gyrotron oscillator.” Physics of Plasmas 14, no. 9 (2007). https://doi.org/10.1063/1.2776911

  22. Choi, EunMi, A. J. Cerfon, I. Mastovsky, M. A. Shapiro, J. R. Sirigiri, and R. J. Temkin. “Efficiency enhancement of a 1.5-MW, 110-GHz gyrotron with a single-stage depressed collector.” Fusion Science and Technology 52, no. 2 (2007): 334-339. https://doi.org/10.13182/FST07-A1511

  23. Han, Seong-Tae, Robert G. Griffin, Kan-Nian Hu, Chan-Gyu Joo, Colin D. Joye, Jagadishwar R. Sirigiri, Richard J. Temkin, Antonio C. Torrezan, and Paul P. Woskov. “Spectral characteristics of a 140-GHz long-pulsed gyrotron.” IEEE Transactions on Plasma Science 35, no. 3 (2007): 559-564. https://doi.org/10.1109/TPS.2007.896931

  24. Shapiro, M. A., G. Shvets, J. R. Sirigiri, and R. J. Temkin. “Spatial dispersion in metamaterials with negative dielectric permittivity and its effect on surface waves.” Optics letters 31, no. 13 (2006): 2051-2053. https://doi.org/10.1364/OL.31.002051

  25. Joye, Colin D., Robert G. Griffin, Melissa K. Hornstein, Kan-Nian Hu, Kenneth E. Kreischer, Melanie Rosay, Michael A. Shapiro, Jagadishwar R. Sirigiri, Richard J. Temkin, and Paul P. Woskov. “Operational characteristics of a 14-W 140-GHz gyrotron for dynamic nuclear polarization.” IEEE Transactions on Plasma Science 34, no. 3 (2006): 518-523. https://doi.org/10.1109/TPS.2006.875776

  26. Korbly, S. E., A. S. Kesar, J. R. Sirigiri, and R. J. Temkin. “Observation of frequency-locked coherent terahertz Smith-Purcell radiation.” Physical review letters 94, no. 5 (2005): 054803. https://doi.org/10.1103/PhysRevLett.94.054803

  27. Sirigiri, Jagadishwar R., Michael A. Shapiro, and Richard J. Temkin. “High-power 140-GHz quasioptical gyrotron traveling-wave amplifier.” Physical review letters 90, no. 25 (2003): 258302. https://doi.org/10.1103/PhysRevLett.90.258302

  28. Sirigiri, Jagadishwar Rao, Kenneth E. Kreischer, J. Machuzak, Ivan Mastovsky, Michael A. Shapiro, and Richard J. Temkin. “Photonic-band-gap resonator gyrotron.” Physical Review Letters 86, no. 24 (2001): 5628. https://doi.org/10.1103/PhysRevLett.86.5628


  1. Integrated high-frequency generator system utilizing the magnetic field of the target application, Jagadishwar R. SirigiriThorsten Maly, United States Patent No. US 8,786,284 B2, Jan. 11, 2011.

  2. Photonic band gap structure simulator, C. Chen, M. A. Shapiro, E. I. Smirnova, and R. J. Temkin, J. R. Sirigiri, United States Patent No. US 7,117,13, Oct. 3, 2006

  3. Vacuum Electron Device with Photonic Band Gap Structure and Method of Use Thereof, Chiping Chen, M. A. Shapiro, J. R. Sirigiri, and R. J. Temkin, United States Patent No. US 6,801,107 B2, Oct. 5, 2004.