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Daniel Lum

NRC Postdoctoral Fellow


My research interests form an eclectic mix of fields including quantum optics, quantum information, remote sensing, and compressive imaging. My interests primarily regard applied physics to answer the question How can I use my knowledge of optics, quantum mechanics, and signal processing to solve difficult problems related to low-light remote sensing and imaging problems? As such, my current project here at NIST is to help bridge the gap between quantum optics and biological imaging. My specific interests can be summarized by the following points:

  • Computational Imaging: This includes both compressive imaging and lensless imaging techniques for a variety of remote sensing applications from microscopic to astronomical. Applications include entanglement characterizations, wavefront sensing, and compressive measurements of an optical Dirac matrix (yielding similar information obtained through Fourier ptychography), and endoscopic imaging through multimode fibers.
  • Remote Sensing: Pulsed LiDAR , Frequency-Modulated Continuous-Wave LiDAR, and Doppler measurements are two interesting topics with a broad range of applications.  I have worked on projects requiring the design and development signal processing algorithms together with optical design to push the envelope of low-light ranging and Doppler measurements.
  •  Quantum information: A significant amount of research has been done in the fields of quantum information which includes topics such as quantum key distribution (QKD). I am interested in protocols related to quantum data locking (QDL) that may help increase the key-rates for QKD. While there is much potential for QDL, protocols are currently limited because of the difficult task of transmitting information over a long-range quantum channel (as opposed to QKD which transmits the information over a reliable classical channel). As such, I am interested in developing robust ways of generating quantum channels.

My current task here at NIST is to establish a lower bound over which time-energy entangled photons may enhance two-photon fluorescence for deep-tissue imaging. As such, I am using a Franson interferometer to measure the degree of Bell-violation as a function of tissue depth. A schematic diagram of my experiment is provided.


Daniel Fig 2
Fig. 1 (a) Folded polarization-based Franson interferometer for verifying the survival of time-energy entanglement through tissues. SPDC: spontaneous parametric down-conversion, BiBO: Bismuth Borate nonlinear crystal, M: Mirror, PBS: polarized beamsplitter, QWP: quarter-wave plate, HWP: half-wave plate, VWP: variable-wave plate. (b) Franson interference observed in the absence of a tissue sample.  


  1. Samuel H. Knarr, Daniel J. Lum, James Schneeloch, and John C. Howell. Compressive direct imaging of a billion-dimensional optical phase space. Physical Review A, 98:023854, Aug 2018.
  2. Daniel J. Lum, Samuel H. Knarr, and John C. Howell. Frequency-modulated continuous-wave lidar compressive depth-mapping. Optics Express, 26(12):15420–15435, Jun 2018.
  3. Thomas Gerrits, Daniel J. Lum, Varun Verma, John C. Howell, Richard P. Mirin, and Sae Woo Nam. Short-wave infrared compressive imaging of single photons. Optics Express, 26(12):15519–15527, Jun 2018.
  4. Daniel J. Lum, John C. Howell, M. S. Allman, Thomas Gerrits, Varun B. Verma, Sae Woo Nam, Cosmo Lupo, and Seth Lloyd. Quantum enigma machine: Experimentally demonstrating quantum data locking. Physical Review A, 94:022315, Aug 2016.
  5. Gregory A. Howland, Samuel H. Knarr, James Schneeloch, Daniel J. Lum, and John C. Howell. Compressively characterizing high-dimensional entangled states with complementary, random filtering. Physical Review X, 6:021018, May 2016.
  6. James Schneeloch, Samuel H. Knarr, Daniel J. Lum, and John C. Howell. Position-momentum Bell nonlocality with entangled photon pairs. Physical Review A, 93:012105, Jan 2016.
  7. Daniel J. Lum, Samuel H. Knarr, and John C. Howell. Fast Hadamard transforms for compressive sensing of joint systems: measurement of a 3.2 million-dimensional bi-photon probability distribution. Optics Express, 23(21):27636–27649, Oct 2015.
  8. Gregory A. Howland, Daniel J. Lum, and John C. Howell. Compressive wavefront sensing with weak values. Optics Express, 22(16):18870–18880, Aug 2014.
  9. Gregory A. Howland, James Schneeloch, Daniel J. Lum, and John C. Howell. Simultaneous measurement of complementary observables with compressive sensing. Physical Review Letters, 112:253602, Jun 2014.
  10. Gregory A. Howland, Daniel J. Lum, Matthew R. Ware, and John C. Howell. Photon counting compressive depth mapping. Optics Express, 21(20):23822–23837, Oct 2013.
  11. Petr M. Anisimov, Daniel J. Lum, S. Blane McCracken, Hwang Lee, and Jonathan P. Dowling. An invisible quantum tripwire. New Journal of Physics, 12(8):083012, 2010.

Pending Publications (Never approved for publication due to export-controlled information)

  1. Daniel J. Lum, Justin M. Winkler, Samuel H. Knarr, and John C. Howell. Slow-light interferometric frequency-modulated laser radar without an optical local oscillator. 
  2. Justin M. Winkler, Daniel J. Lum, Samuel H. Knarr, and John C. Howell. Measurement of kilohertz-level frequency shifts using a slow-light interferometer without a local oscillator.
Created August 2, 2018, Updated January 14, 2020