Konrad Lehnert

Konrad Lehnert's picture
Professor of Physics, starting July 1, 2024
Research Areas: 
Quantum information, Particle astrophysics, Atomic, Molecular, and Optical Physics, Condensed Matter
Research Type: 
Biographical Sketch: 

Konrad W. Lehnert received his Ph. D. in 1999 from the University of California at Santa Barbara. He was as a post-doctoral scientist at Yale from 1999-2003. At Yale, he worked with Robert Schoelkopf on qubit structures built from superconducting circuits. In 2003 he joined JILA, a joint institute of the University of Colorado and NIST, as an Associate Fellow. In 2007 he was promoted to JILA Fellow and served as JILA Chair from 2022- 2024. At JILA, he established a research group studying microwave quantum circuits, mesoscopic electronics, and quantum nanomechanics. In particular, his group pioneered measurements of electrical circuits and mechanical oscillators that reached quantum-limited sensitivity. In addition his group developed control methods that cooled mechanical oscillators to their quantum ground state and entangled them with electrical circuits. Recently, he has applied techniques of quantum enhanced measurement and control to the search for hypothesized fundamental particles that make up dark matter.

Research : 

In our group, we build electrical and electromechanical machines and coax them into exhibiting quantum behavior. We are motivated by asking: “what is the largest and most tangible object that can be in two places at once?” In addition, we seek to use these machines to store, process, and transmit information in an essentially quantum way. Finally, we develop measurement tools for sensing feeble forces and electrical signals at the limits imposed by quantum mechanics.

Ph.D. 1999, University of California, Santa Barbara
Honors & Awards: 

He has published more than 100 papers in scholarly journals. He is a Fellow of the American Physical Society and the American Association for the Advancement of Science. He won the Department of Commerce Silver Medal and the Colorado Governor’s Award for High Impact Research. In 2020, he was awarded a Vannevar Bush Faculty Fellowship.

Selected Publications: 
  • Superconducting-qubit readout via low-backaction electro-optic transduction
    Delaney R., M. Urmey, S. Mittal, B.M. Brubaker, J. Kindem, P.S. Burns, C.A. Regal, and K.W. Lehnert, Nature 606, 489-493 (2022).
  • Efficient and Low-Backaction Quantum Measurement Using a Chip-Scale Detector
    Rosenthal E.I., C.M.F. Schneider, M. Malnou, Z. Zhao, F. Leditzky, B.J. Chapman, W. Wustmann, X. Ma, D.A. Palken, M.F. Zanner, and L.R. Vale, Physical Review Letters 126, (2021).
  • A quantum enhanced search for dark matter axions
    Backes K.M., D.A. Palken, A. Kenany, B.M. Brubaker, S.B. Cahn, A. Droster, G.C. Hilton, S. Ghosh, H. Jackson, S.K. Lamoreaux, and A.F. Leder, Nature 590, 238-242 (2021).
  • Non-classical energy squeezing of a macroscopic mechanical oscillator
    Ma X., J.J. Viennot, S. Kotler, J.D. Teufel, and K.W. Lehnert, Nature Physics 17, 322-326 (2021).
  • Resolving Phonon Fock States in a Multimode Cavity with a Double-Slit Qubit
    Sletten L.R., B. Moores, J.J. Viennot, and K.W. Lehnert, Physical Review X 9, 021056 (2019).