Quantum enhanced LIDAR resolution with multi-spatial-mode phase sensitive amplification

Cesar A. Santivanez, Saikat Guha, Zachary Dutton, Muthiah Annamalai, Michael Vasilyev, Brent J. Yen, Ranjith Nair, Jeffrey H. Shapiro

Research output: Chapter in Book/Report/Conference proceedingConference contribution

10 Scopus citations


Phase-sensitive amplification (PSA) can enhance the signal-to-noise ratio (SNR) of an optical measurement suffering from detection inefficiency. Previously, we showed that this increased SNR improves LADAR-imaging spatial resolution when infinite spatial-bandwidth PSA is employed. Here, we evaluate the resolution enhancement for realistic, finite spatial-bandwidth amplification. PSA spatial bandwidth is characterized by numerically calculating the input and output spatial modes and their associated phase-sensitive gains under focused-beam pumping. We then compare the spatial resolution of a baseline homodyne-detection LADAR system with homodyne LADAR systems that have been augmented by pre-detection PSA with infinite or finite spatial bandwidth. The spatial resolution of each system is quantified by its ability to distinguish between the presence of 1 point target versus 2 closely-spaced point targets when minimum error-probability decisions are made from quantum limited measurements. At low (5-10 dB) SNR, we find that a PSA system with a 2.5kWatts pump focused to 25μm × 400μm achieves the same spatial resolution as a baseline system having 5.5 dB higher SNR. This SNR gain is very close to the 6 dB SNR improvement possible with ideal (infinite bandwidth, infinite gain) PSA at our simulated system detection efficiency (0.25). At higher SNRs, we have identified a novel regime in which finite spatial-bandwidth PSA outperforms its infinite spatial-bandwidth counterpart. We show that this performance crossover is due to the focused pump system's input-to-output spatial-mode transformation converting the LADAR measurement statistics from homodyne to heterodyne performance.

Original languageEnglish (US)
Title of host publicationQuantum Communications and Quantum Imaging IX
Publication statusPublished - Nov 7 2011
Externally publishedYes
EventQuantum Communications and Quantum Imaging IX - San Diego, CA, United States
Duration: Aug 24 2011Aug 25 2011

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
ISSN (Print)0277-786X


ConferenceQuantum Communications and Quantum Imaging IX
CountryUnited States
CitySan Diego, CA



  • homodyne detection
  • multi-mode PSA
  • Phase-Sensitive Amplification (PSA)

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

Cite this

Santivanez, C. A., Guha, S., Dutton, Z., Annamalai, M., Vasilyev, M., Yen, B. J., ... Shapiro, J. H. (2011). Quantum enhanced LIDAR resolution with multi-spatial-mode phase sensitive amplification. In Quantum Communications and Quantum Imaging IX [81630Z] (Proceedings of SPIE - The International Society for Optical Engineering; Vol. 8163). https://doi.org/10.1117/12.903351