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Seulki Cho, Son T. Le, Curt A. Richter, Arvind Balijepalli
We demonstrate that single-gated, commercially-sourced, field-effect transistors (FETs) operated with a lock- in amplifier (LIA) under closed-loop control can achieve an average pH resolution of 9x10^-4. This performance represents an 8-fold improvement
In this work, we study the electromagnetic scattering characteristics of asymmetric carbon nanotube (CNT) dimers. We show that the configurational asymmetry in the CNT dimer assembly creates a unique field distribution in the vicinity of the dimer, which
Radislav A. Potyrailo, J. Brewer, B. Cheng, M. A. Carpenter, N. Houlihan, Andrei Kolmakov
Existing sensors for gaseous species often degrade their performance because of the loss of the measurement accuracy in the presence of interferences. Thus, new sensing approaches are required with improved sensor selectivity. We are developing a new
Andrei A. Kolmakov, Radislav A. Potyrailo, Steven Go, Daniel Sexton, Xiaxi Li, Nasr Alkadi, Bruce Amm, Richard St-Pierre, Brian Scherer, Majid Nayeri, Guang Wu, Christopher Collazo-Davila, Doug Forman, Chris Calvert, Craig Mack, Philip Mcconnell
Electrical response of metal oxide semiconducting (MOS) materials to gases was discovered 70 years ago [1] and miniature low-cost MOS chemiresistors became the most popular gas sensors when chemical selectivity is not required [2, 3]. When discrimination
Son T. Le, Michelle A. Morris, Antonio Cardone, Nicholas B. Guros, Jeffery B. Klauda, Brent A. Sperling, Curt A. Richter, Harish C. Pant, Arvind Balijepalli
We show that commercially sourced n-channel silicon field-effect transistors (nFETs) operating under closed-loop control achieve a resolution of (7.2+/-0.3)x10-3 pH units with a bandwidth of 10 Hz. The results represent an 3-fold improvement in performance
Shamith Payagala, Alireza Panna, Albert Rigosi, Dean G. Jarrett
Calibration services for resistance metrology have continued to advance their capabilities and establish new and improved methods for maintaining standard resistors. Despite the high quality of these methods, there still exist inherent limitations to the
Anthony B. Kos, Fabio C. Da Silva, Jason B. Coder, Craig W. Nelson, Grace E. Antonucci, Archita Hati
Imaging solutions based on wave scattering seek real-time performance, high dynamic range, and spatial accuracy at scales spanning from nanometers to thousands of kilometers. Compressed sensing algorithms use sparsity to reduce sample size during image
Over the past two decades, MEMS resonators have received considerable attention for physical, chemical and biological sensing applications. Typically, the operation of MEMS resonant sensors relies on the tracking of a resonance frequency using a feedback
Varun Verma, Adriana Lita, Sae Woo Nam, R P. Mirin, Emma Wollman, William Farr, Matthew Shaw
We present a 1024-element imaging array of superconducting nanowire single photon detectors (SNSPDs) using a 32x32 row-column multiplexing architecture. Large arrays are desirable for applications such as imaging, spectroscopy, or particle detection.
John A. Mates, Daniel T. Becker, Douglas A. Bennett, Bradley J. Dober, Johnathon D. Gard, Gene C. Hilton, Daniel S. Swetz, Leila R. Vale, Joel N. Ullom
Low-temperature detector technologies provide extraordinary sensitivity for applications ranging from precision measurements of the cosmic microwave background to high-resolution, high-rate x-ray, and c-ray spectroscopy. To utilize this sensitivity, new
Joseph W. Fowler, Bradley K. Alpert, Young I. Joe, Galen C. O'Neil, Daniel S. Swetz, Joel N. Ullom
A principal component analysis (PCA) of clean microcalorimeter pulse records can be a first step beyond statistically optimal linear filtering of pulses toward a fully nonlinear analysis. For PCA to be practical on spectrometers with hundreds of sensors
Kelsey M. Morgan, Daniel T. Becker, Douglas A. Bennett, Johnathon D. Gard, Jozsef Imrek, John A. Mates, Christine G. Pappas, Carl D. Reintsema, Daniel R. Schmidt, Joel N. Ullom, Joel C. Weber, Abigail L. Wessels, Daniel S. Swetz
Microwave SQUID multiplexing has become a key technology for reading out large arrays of X-ray and gamma-ray microcalorimeters with mux factors of 100 or more. The desire for fast X-ray pulses that accommodate photon counting rates of hundreds or thousands