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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).


Electro-Optic Imaging Millimeter-Wave Propagation On-Wafer

Bryan Bosworth, Nick Jungwirth, Jerome Cheron, Franklyn Quinlan, Nate Orloff, Chris Long, Ari Feldman
We demonstrate an electro-optic imaging system for mmWaves propagating along a coplanar waveguide. Using dual optical frequency combs and a polarization

Quantifying the Effect of Guest Binding on Host Environment

Angela Stelson, Zack Fishman, Jacob Pawlik, Gosia Musial, Jim Booth, Chris Long, Kathleen Schwarz, Nate Orloff, Hugh Ryan, Angela Grommet, Jonathan Nitschke, Felix Rizzuto
The environment around a host-guest complex is defined by of intermolecular interactions between solvent molecules and counter ions. These interactions govern

Broadband Electromagnetic Properties of Engineered Flexible Absorber Materials

Luckshitha Suriyasena Liyanage, Connor Smith, Jacob Pawlik, Sarah Evans, Angela Stelson, Chris Long, Nate Orloff, David Arnold, Jim Booth
Flexible and stretchable materials have attracted significant interest for applications in wearable electronics and bioengineering fields. Recent developments

Measuring the permittivity tensor of anisotropic DyScO3 to 110 GHz

Florian Bergmann, Meagan Papac, Nick Jungwirth, Bryan Bosworth, Tomasz Karpisz, Anna Osella, Lucas Enright, Eric Marksz, Angela Stelson, Chris Long, Nate Orloff
DyScO3 (DSO) is an attractive substrate on which to grow epitaxial thin films with extraordinary materials physics. However, its highly anisotropic permittivity

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