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Chris Long (Fed)

Dr. Christian J. Long is the project leader for the Radio-Frequency Power and Impedance project at the National Institute of Standards and Technology (NIST). Dr. Long received the B.S. and Ph.D. degrees in physics from the University of Maryland at College Park, College Park, MD, USA, in 2004 and 2011, respectively. His doctoral research focused on development of both near-field scanning probe microscopy techniques and new methods to analyze data from combinatorial materials experiments. From 2012 to 2015 he was a postdoctoral research fellow with NIST, Gaithersburg, USA, where he focused on techniques for characterizing nanoscale materials. In 2016, he joined the staff at NIST, Boulder, USA, to work on development of standards for radio-frequency, microwave, and mm-wave calibrations.  

Selected Publications:

  • Energy harvesting properties of all-thin-film multiferroic cantilevers, T.-D. Onuta, Y. Wang, C. J. Long, and I. Takeuchi, Applied Physics Letters 99, 203506 (2011).
  • Atomic resolution imaging at 2.5 GHz using near-field microwave microscopy, J. Lee, C. J. Long, H. Yang, X.-D. Xiang, and I. Takeuchi, Applied Physics Letters 97, 183111 (2010).
  • Rapid identification of structural phases in combinatorial thin-film libraries using x-ray diffraction and non-negative matrix factorization, C. J. Long, D. Bunker, X. Li, V. L. Karen, and I. Takeuchi, Review of Scientific Instruments 80, 103902 (2009).

Publications

Characterizing interconnects to 325 GHz

Author(s)
Nicholas Jungwirth, Bryan Bosworth, Meagan Papac, Aaron Hagerstrom, Eric Marksz, Jerome Cheron, Angela Stelson, Florian Bergmann, Ari Feldman, Dylan Williams, Christian Long, Nathan Orloff
We developed an interconnect characterization procedure that first embeds the interconnect into the error boxes of a multiline thru-reflect-line calibration and

Broadband Characterization of Flexible Conductor-Dielectric Composites

Author(s)
Luckshitha Suriyasena Liyanage, Nathan Orloff, Nicholas Jungwirth, Sarah Evans, Christian Long, Angela Stelson, Jacob Pawlik, James Booth
Broadband measurements are important for characterizing a wide range of materials for communications applications at microwave and mm-wave frequencies. Here we

Traceable RF Power Metering Procedures With Thermoelectric Sensors

Author(s)
Zenn Roberts, Aaron Hagerstrom, Cole Gray, Angela Stelson, Vincent Neylon, Christian Long
The National Institute of Standards and Technology (NIST) maintains the United State's primary standards for traceable RF and mm-wave power measurements. These

Demonstrating Broadside-Coupled Coplanar Waveguide Interconnects to 325 GHz

Author(s)
Nicholas Jungwirth, Bryan Bosworth, Aaron Hagerstrom, Meagan Papac, Eric Marksz, JEROME CHERON, Kassiopeia Smith, Angela Stelson, Ari Feldman, Dylan Williams, Nathan Orloff, Christian Long
State-of-the-art integrated circuits leverage dissimilar materials to optimize system performance. Such heterogeneous integration often involves multiple chips

Patents (2018-Present)

Scanning Microwave Ellipsometer And Performing Scanning Microwave Ellipsometry

NIST Inventors
Chris Long , Nate Orloff and Edward Garboczi
New strong, light, and compact formed carbon fiber components require shorter, higher-aspect ratio carbon fibers. Shorter carbon fibers must be aligned to realize the desired tensile strength. Before this invention, industry lacked a tool to characterize carbon fiber alignment for inline quality

Scanning Microwave Ellipsometer And Performing Scanning Microwave Ellipsometry

NIST Inventors
Chris Long , Nate Orloff and Edward Garboczi
A scanning microwave ellipsometer includes: a microwave ellipsometry test head including: a polarization controller; a transmission line; and a sensor that produces sensor microwave radiation, subjects a sample to the sensor microwave radiation, receives a sample reflected microwave radiation from
A photo of the noncntact dielectric and conductivity meter for high-throughput processing and a circuit diagram of the circuit used to track the resonant frequency and quality factor of the microwave resonator.

Noncontact Resonameter, Process for making and use of same

NIST Inventors
Jan Obrzut , Nate Orloff and Chris Long
A noncontact resonameter includes: a resonator to: produce an excitation signal including a field; subject a sample to the excitation signal; produce a first resonator signal in a presence of the sample and the excitation signal, the first resonator signal including: a first quality factor of the
Created July 30, 2019, Updated December 8, 2022