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Jeffrey A. Jargon, Dylan F. Williams, Paul D. Hale, Michael D. Janezic
We characterize and provide uncertainties for a noninsertable, directional device over a frequency range of 90 to 100 GHz using the NIST Microwave Uncertainty Framework in conjunction with a commercial vector network analyzer. Our device consists of a
Jacob M. Taylor, Tolga Bagci, A Simonsen, Silvan Schmid, L Villanueva, Emil Zeuthen, Anders Sorensen, Koji Usami, A Schliesser, E.S. Polzik
Low-loss transmission and sensitive recovery of weak radio-frequency (rf) and mi- crowave signals is an ubiquitous technological challenge, crucial in fields as diverse as radio astronomy, medical imaging, navigation and communication, including those of
Jacob M. Taylor, Silvan Schmid, Tolga Bagci, Emil Zeuthen, Patrick Herring, Maja Cassidy, C. M. Marcus, Bartolo Amato, Anja Boisen, Yong C. Shin, Jing Kong, Anders Sorensen, Koji Usami, E.S. Polzik
Due to their exceptional mechanical and optical properties, dielectric silicon nitride (SiN) mi- cromembranes have become the centerpiece of many optomechanical experiments. Efficient capac- itive coupling of the membrane to an electrical system would
Erich N. Grossman, Oscar D. Friedman, Andrew O. Nelson
We describe the design, simulation, and measured performance of concentrators designed to couple submillimeter wavelength radiation from free space into highly overmoded, rectangular, WR-10 waveguide. They consist of a combination of a Winston cone, (also
Sergio Cova, Massimo Ghioni, Mark A. Itzler, Joshua Bienfang, Alessandro Restelli
There is nowadays a widespread and growing interest in low-level light detection and imaging. This interest is driven by the need for high sensitivity in various scientific and industrial applications such as fluorescence spectroscopy in life and material
In this paper we investigate axial p-n junction GaN nanowires grown by plasma-assisted MBE, with particular attention to the effect of Mg doping on the device characteristics of individual nanowire LEDs. We observe that single-nanowire LEDs produce
Matthew D. Brubaker, Paul T. Blanchard, John B. Schlager, Aric W. Sanders, Alexana Roshko, Shannon M. Duff, Jason Gray, Victor M. Bright, Norman A. Sanford, Kristine A. Bertness
In this letter we report on the fabrication, device characteristics, and optical coupling of a two-nanowire device comprising light-emitting diode and photoconductive GaN nanowires. Axial p-n junction GaN nanowires were grown by molecular beam epitaxy
Jason Gray, Kristine A. Bertness, Norman Sanford, Charles T. Rogers
We report on the low-frequency 1/f (flicker) parameter noise displayed by the resonance frequency and resistance of doubly clamped c-axis gallium nitride nanowire (NW) mechanical resonators. The resonators are electrostatically driven and their mechanical
Christopher M. Dodson, Patrick Parkinson, Kristine A. Bertness, Hannah J. Joyce, Laura M. Herz, Norman Sanford, Michael B. Johnston
The first noncontact photoconductivity measurements of gallium nitride nanowires (NWs) are presented, revealing a high crystallographic and optoelectronic quality achieved by use of catalyst-free molecular beam epitaxy. In comparison with bulk material
Rusen Yan, Qin Zhang, Wei Li, Irene G. Calizo, Tian T. Shen, Curt A. Richter, Angela R. Hight Walker, Xuelei X. Liang, David J. Gundlach, Nhan Van Nguyen, Huili G. Xing, Alan Seabaugh
We determined the band alignment of a graphene-oxide-silicon structure using internal photoemission spectroscopy. From the flatband voltage and Dirac voltage we infer a 4.3 10e11 cm-2 negative extrinsic charge present on the graphene surface. Also, we
Kevin O. Knabe, Fabrizio R. Giorgetta, Nathan R. Newbury, Chris Armacost, Michael Radunsky, Sam Crivello, Timothy Day, Paul A. Williams
We demonstrate sub-MHz spectral resolution of N 2O absorption spectra acquired with a swept external-cavity quantum cascade laser (QCL) over 0.87 THz. The QCL frequency is monitored by sum -frequency generation with an optical fiber frequency comb.
David J. Livigni, Nathan A. Tomlin, Christopher L. Cromer, John H. Lehman
A cryogenic radiometer was constructed for direct-substitution optical fiber power measurements. The cavity is intended to operate at the 3 K temperature stage of a dilution refrigerator or 4.2 K stage of a liquid cryostat. The optical fiber is removable
Nathan R. Newbury, Alexander M. Zolot, Esther Baumann, Fabrizio R. Giorgetta, Florian B. Adler, Ian R. Coddington, Kevin O. Knabe, Lora L. Nugent-Glandorf, Paul A. Williams, Scott A. Diddams, Tyler W. Neely
An optical frequency comb based on the output of a mode-locked femtosecond laser can be used in spectroscopic studies and sensing applications. The broad array of frequency modes simultaneously provides high spectral resolution and broad wavelength