U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications by: Chris Long (Fed)

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 26 - 50 of 117

Quantifying Receiver Nonlinearities in VNA Measurements for the WR-15 Waveguide Band

March 15, 2022
Author(s)
Angela Stelson, Aaron Hagerstrom, Jeffrey Jargon, Chris Long
Scattering (S-) parameters are fundamental to numerous microwave quantities including antenna factors, microwave power, and phase. The uncertainty in S-parameter measurements is influenced by the test setup, including instrument noise, drift, position of

High-Gain 500-GHz InP HBT Power Amplifiers

January 31, 2022
Author(s)
Jerome Cheron, Rob Jones, Richard Chamberlin, Dylan Williams, Miguel Urteaga, Kassi Smith, Nick Jungwirth, Bryan Bosworth, Chris Long, Nate Orloff, Peter Aaen, Ari Feldman
We report two terahertz monolithic integrated circuit (TMIC) amplifiers operating at 500 GHz. The 6-stage single-ended power amplifiers use Teledyne's 130 nm indium-phosphide double heterojunction bipolar transistors in a common-base configuration. The

Updates to the traceability of mm-wave power measurements at NIST

December 17, 2021
Author(s)
Aaron Hagerstrom, Angela Stelson, Jeffrey Jargon, Chris Long
Metrological traceability helps ensure the reliability of measurements by allowing them to be compared with established international standards with well-understood uncertainties. A thorough uncertainty analysis is therefore necessary to provide traceable

Collector Series-Resistor to Stabilize a Broadband 400 GHz Common-Base Amplifier

October 14, 2021
Author(s)
Jerome Cheron, Dylan Williams, Richard Chamberlin, Miguel Urteaga, Kassi Smith, Nick Jungwirth, Bryan Bosworth, Chris Long, Nate Orloff, Ari Feldman
The indium phosphide (InP) 130 nm double-heterojunction bipolar transistor (DHBT) offers milliwatts of output power and high signal amplification in the lower end of the terahertz frequency band when the transistor is used in a common-base configuration

Electro-optically derived millimeter-wave sources with phase and amplitude control

October 12, 2021
Author(s)
Bryan Bosworth, Nick Jungwirth, Kassi Smith, Jerome Cheron, Franklyn Quinlan, Ari Feldman, Dylan Williams, Nate Orloff, Chris Long
Integrated circuits are building blocks in millimeter-wave handsets and base stations, requiring nonlinear characterization to optimize performance and energy efficiency. Today's sources use digital-to-analog converters to synthesize arbitrary electrical

Local negative permittivity and topological-phase transition in polar skyrmions

October 12, 2020
Author(s)
Sujit Das, Zijian Hong, Vladimir Stoica, Mauro A. Goncalves, Yu-Tsun Shao, Eric Parsonnet, Eric J. Marksz, Sahar Saremi, Margaret McCarter, A Reynoso, Chris Long, Aaron Hagerstrom, D Meyers, V Ravi, B Prasad, H Zhou, Z Zhang, H Wen, F Gomez-Ortiz, P Garcia-Fernandez, J Bokor, J Iniguez, J Freeland, Nate Orloff, J Junquera, Long-Qing Chen, Sayeef Salahuddin, David A. Muller, L Martin, R. Ramesh
Topological solitons such as magnetic skyrmions have drawn enormous attention as stable quasi- particle-like objects. The recent discovery of polar vortices and skyrmions in ferroelectric- oxide superlattices, exhibiting exotic physical phenomena, has

Physical Models and Dimensional Traceability of WR15 Rectangular Waveguide Standards for Determining Systematic Uncertainties of Calibrated Scattering-Parameters

August 10, 2020
Author(s)
Jeffrey A. Jargon, Dylan F. Williams, Angela C. Stelson, Christian J. Long, Aaron M. Hagerstrom, Paul D. Hale, John R. Stoup, Eric S. Stanfield, Wei Ren
In this report, we document the models and dimensional traceability of our WR15 rectangular waveguide standards for performing multiline thru-reflect-line calibrations from 50 GHz to 75 GHz using vector network analyzers. We identify the equations used in

On-Wafer Metrology of a Transmission Line Integrated Terahertz Source

May 10, 2020
Author(s)
Kassiopeia A. Smith, Bryan T. Bosworth, Nicholas R. Jungwirth, Jerome G. Cheron, Nathan D. Orloff, Christian J. Long, Dylan F. Williams, Richard A. Chamberlin, Franklyn J. Quinlan, Tara M. Fortier, Ari D. Feldman
A combination of on-wafer metrology and high-frequency network analysis was implemented to measure the response of transmission-line integrated Er-GaAs and InGaAs photomixers up to 1 THz to support the telecommunication and electronics industry.

Measurements of Nonlinear Polarization Dynamics in the Tens of Gigahertz

April 9, 2020
Author(s)
Aaron Hagerstrom, Eric J. Marksz, Xiaohang Zhang, Xifeng Lu, Chris Long, James Booth, Ichiro Takeuchi, Nate Orloff
Frequency-dependent linear permittivity measurements are commonplace in the literature, providing key insights into the structure of dielectric materials. These measurements describe a material's dynamic response to a small applied electric eld. In

Materials Characterization With Multiple Offset Reflects at Frequencies to 110 GHz

January 8, 2020
Author(s)
Nina P. Basta, Aaron Hagerstrom, Jasper A. Drisko, Jim Booth, Edward Garboczi, Chris Long, Nate Orloff
Understanding the electrical properties of materials is a necessary part of any microwave circuit design. In this article, we explore the possibility of employing multiple-offset-reflect devices for on-wafer materials characterization at frequencies up to