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Search Publications by: Stephan Schlamminger (Fed)

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Displaying 1 - 25 of 75

Comparison of a 1 nF Capacitor with a 1 kO Resistor Using a Digital Impedance Bridge

March 27, 2024
Author(s)
Yicheng Wang, Stephan Schlamminger, Dean G. Jarrett, Alireza Panna, Andrew D. Koffman
This paper reports our effort to improve a digital impedance bridge. The limit of the bridge resolution and stability is less than 3 parts in 10^9 for the nominal 1:1 impedance comparison of two 100 pF capacitors. The type-A uncertainty for comparison of a

Application of Electrical Standards to Torque Realization: A Device to Measure up to 1Nm

February 14, 2024
Author(s)
Zane Comden, Stephan Schlamminger, Frank Seifert, David B. Newell, Leon Chao
This paper describes the next generation prototype of the Electronic NIST Torque Realizer (ENTR) project. The first prototype version (ENTR-v1) has been able to realize low-range torques (on the order of 1×10-3 Nm) to uncertainties of less than 1000 parts

Measuring the frequency of a pendulum

November 13, 2023
Author(s)
Jon R. Pratt, Stephan Schlamminger, Charles Condos, Jack Manley, Dalziel Wilson
We previously reported the use of a chip-scale torsion pendulum as a clock gravimeter, exploiting the parametric coupling of its frequency to the local acceleration of gravity and demonstrating micro-g resolution with a silicon nitride prototype. Here, we

The design and performance of an electronic torque standard directly traceable to the revised SI

May 25, 2023
Author(s)
Zane Comden, John-Edward Draganov, Stephan Schlamminger, Frank Seifert, Charles Waduwarage Perera, David B. Newell, Leon Chao
The United States National Institute of Standards and Technology (NIST) has been developing a new device for primary standard realization of torque utilizing established trace- ability to the quantum-electrical International System of Units (SI) standards

New Method for Determining Time Constant of Resistors

March 21, 2023
Author(s)
Yicheng Wang, Dean G. Jarrett, Andrew D. Koffman, Stephan Schlamminger
We report a new method for determining the time constant of ac resistors with values around 10 kΩ, using a digital impedance bridge for comparison of two nominally equal resistors. The method involves adding a probing capacitor in parallel to one of the

A Macroscopic Mass From Quantum Behavior In An Integrated Approach

December 10, 2022
Author(s)
Frank Seifert, Alireza Panna, Lorenz Keck, Leon Chao, Shamith Payagala, Dean G. Jarrett, Dipanjan Saha, Randolph Elmquist, Stephan Schlamminger, Albert Rigosi, David B. Newell, Darine El Haddad
The revision of the International System of Units (SI) on May 20th, 2019, has enabled new improved experiments to consolidate and simplify electrical and mechanical metrology currently underway. Historically within the SI, the definition of energy was only

Calculation of magnetic forces and torques on the Kibble coil

October 22, 2022
Author(s)
Stephan Schlamminger, Lorenz Keck, Frank Seifert, Leon Chao, Darine El Haddad, Shisong Li
Analytically the force and torques on a coil in a field of magnetic flux density can be calculated one of two ways. The line integral can be conducted along the coil's wire, summing up the differential force contribution. For each differential line segment

The kilogram: inertial or gravitational mass?

August 5, 2022
Author(s)
Stephan Schlamminger, Giovanni Mana
The redefinition of the international system of units fixes the values of the unperturbed ground state hyperfine transition frequency of the $^133}$Cs atom, speed of light in vacuum, and Planck constant. Therefore, differently from the past, the kilogram

Magnetic Uncertainties for Compact Kibble Balances: An Investigation

July 18, 2022
Author(s)
Shisong Li, Stephan Schlamminger
The Kibble balance has become one of the major instruments for realizing the mass unit, the kilogram, in the revised international system of units (SI). Researchers at about a dozen national metrology institutes are actively working with Kibble balances

Design of an electrostatic feedback for an experiment to measure G

June 20, 2022
Author(s)
Stephan Schlamminger, Leon Chao, Vincent Lee, David B. Newell, Clive Speake
The torsion pendulum at the heart of the BIPM apparatus to measure the gravitational constant, $G$, is used to measure the gravitational torque between source and test-mass assemblies with two methods. In the Cavendish method, the pendulum moves freely. In

A New Spin on Kibble: A Self Calibrating Torque Realization Device at NIST

June 3, 2022
Author(s)
Zane Comden, Stephan Schlamminger, Charles Waduwarage Perera, Frank Seifert, David B. Newell, Jay H. Hendricks, Barbara L. Goldstein, Leon Chao
After the 2019 redefinition of the International System of Units (SI), torque no longer needs to be traceable to a calibrated weight suspended from a known lever arm. Specifically, a modification of the Kibble principle used for realizing the kilogram

The irony of the magnet system for Kibble balances -- a review

March 1, 2022
Author(s)
Stephan Schlamminger, Shisong Lo
The magnet system is an essential component in the Kibble balance, supplying the magnetic flux that plays a vital role as the geometric factor $Bl$. Ironically, the $Bl$ factor cancels out and does not appear in the final Kibble equation. Nevertheless

The Crane Operator's Tricks and other Shenanigans with a Pendulum

February 18, 2022
Author(s)
Stephan Schlamminger, Leon Chao, David B. Newell, Vincent Lee
The dynamics of a swinging payload suspended from a stationary crane can be described as a simple pendulum, typically an unwelcome phenomenon on a construction site. An experienced crane operator can deliver a swinging payload and stop dead on target in a

Evaluations of a Detector-Limited Digital Impedance Bridge

April 6, 2021
Author(s)
Mona Feige, Stephan Schlamminger, Yicheng Wang
We tested a simple digital impedance bridge using two nominally equal resistors to form a 1:1 ratio. We focused on resolution and stability of the detectors. Fluctuations of the source voltages were largely removed through postprocessing of the digitized

Design of an electrostatic balance to measure optical power of 100 kW

February 19, 2021
Author(s)
Lorenz Keck, Gordon A. Shaw, Renee Theska, Stephan Schlamminger
To accommodate the need for increased portability and accuracy in laser power measurement instrumentation above 100 Watt at the National Institute of Standards and Technology (NIST), a new instrument is required. This instrument is intended to create a new

Gravity measured with record precision

February 10, 2021
Author(s)
Stephan Schlamminger
The gravitational constant G describes the strength of the gravitational uncertainty. Two new measurements with the world's smallest uncertainties are reported.

Redefining the kilogram and other SI units

February 10, 2021
Author(s)
Stephan Schlamminger
Units are at the heart of science and technology. Most measurements require units to express their result. The International System of Units (SI) provides a widely used coherent framework of units. While the present SI is fit for purpose for all

Resolution of the paradox of the diamagnetic force on the Kibble coil

January 13, 2021
Author(s)
Stephan Schlamminger, Shisong Li, Rafael Marangoni, Darine El Haddad, Qing Wang, Wei Zhao
Employing very simple electro-mechanical principles known from classical physics, the Kibble balance establishes a very precise and absolute link between quantum electrical standards and macroscopic mass or force measurements. The success of the Kibble