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Search Publications by: Nikolai Klimov (Fed)

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Displaying 1 - 25 of 47

Emission Ghost Imaging: reconstruction with data augmentation

February 1, 2024
Author(s)
Kevin J. Coakley, Heather H. Chen-Mayer, Bruce D. Ravel, Daniel Josell, Nikolai Klimov, Sarah Robinson, Daniel S. Hussey
Ghost Imaging enables 2D reconstruction of an object even though particles transmitted or emitted by the object of interest are detected with a single pixel detector without spatial resolution. This is possible because the incident beam is spatially

Grating magneto-optical traps with complicated level structures

October 25, 2023
Author(s)
Daniel Barker, Peter Elgee, Ananya Sitaram, Eric Norrgard, Nikolai Klimov, Gretchen K. Campbell, Stephen Eckel
We study the forces and optical pumping within grating magneto-optical traps (MOTs) operating on transitions with non-trivial level structure. In contrast to the standard six-beam MOT configuration, rate equation modelling predicts that the asymmetric

Precise Quantum Measurement of Vacuum with Cold Atoms

December 20, 2022
Author(s)
Daniel Barker, Bishnu Acharya, James A. Fedchak, Nikolai Klimov, Eric Norrgard, Julia Scherschligt, Eite Tiesinga, Stephen Eckel
We describe the cold-atom vacuum standards (CAVS) under development at the National Institute of Standards and Technology. The CAVS measures pressure in the ultra-high and extreme-high vacuum regimes by measuring the loss rate of sub-millikelvin sensor

Lambda-enhanced gray molasses in a tetrahedral laser beam geometry

March 14, 2022
Author(s)
Daniel Barker, Eric Norrgard, Nikolai Klimov, James A. Fedchak, Julia Scherschligt, Stephen Eckel
We report observation of sub-Doppler cooling of lithium using an irregular-tetrahedral laser beam arrangement, which is produced by a nanofabricated diffraction grating. We are able to capture 11(2) % of the lithium atoms from a grating magneto-optical

MICROMETROLOGY IN PURSUIT OF QUANTUM RADIATION STANDARDS

November 9, 2021
Author(s)
Ryan P. Fitzgerald, Zeeshan Ahmed, Denis E. Bergeron, Nikolai Klimov, Dan Schmidt, Ronald Tosh
With the recent redefinition of the SI base units in terms of constants of nature, the race is on to maximize achievable precision by developing primary standards based on quantum metrology, thereby to realize the Quantum SI. For the becquerel (Bq) and

Progress towards comparison of quantum and classical vacuum standards

September 22, 2021
Author(s)
Daniel Barker, Nikolai Klimov, Eite Tiesinga, James A. Fedchak, Julia Scherschligt, Stephen Eckel
We present our progress towards a comparison of NIST's cold atom primary vacuum standard and a dynamic expansion vacuum standard. The cold atom vacuum standard (CAVS) converts the loss rate of atoms from a magnetic trap to a vacuum pressure using ab initio

Quantum-Based Photonic Sensors for Pressure, Vacuum, and Temperature Measurements: A Vison of the Future with NIST on a Chip

September 17, 2021
Author(s)
Jay H. Hendricks, Zeeshan Ahmed, Daniel Barker, Kevin O. Douglass, Stephen Eckel, James A. Fedchak, Nikolai Klimov, Jacob Edmond Ricker, Julia Scherschligt
The NIST on a Chip (NOAC) program's central idea is the idea that measurement technology can be developed to enable metrology to be performed "outside the National Metrology Institute" by the crea-tion of deployed and often miniaturized standards. These

NIST on a Chip: Photonic and Quantum-Based Sensors for Measurements of Pressure, Vacuum, Temperature and Beyond!

April 29, 2021
Author(s)
Jay H. Hendricks, Zeeshan Ahmed, Daniel Barker, Stephen Eckel, James A. Fedchak, Nikolai Klimov, Julia Scherschligt
At the core of the NIST on a Chip (NoAC) program is the idea that measurement technology can be developed to enable metrology to be done "outside the National Metrology Institute" by virtue of deployed and often miniaturized standards (that can also serve

Magneto-optical trapping using planar optics

January 29, 2021
Author(s)
William McGehee, Wenqi Zhu, Daniel Barker, Daron Westly, Alexander Yulaev, Nikolai Klimov, Amit Agrawal, Stephen Eckel, Vladimir Aksyuk, Jabez J. McClelland
Laser-cooled atoms are a key component of many calibration-free measurement platforms— including clocks, gyroscopes, and gravimeters—and are a promising technology for quantum networking and quantum computing. The optics and vacuum hardware required to

Confinement of an alkaline-earth element in a grating magneto-optical trap

October 15, 2020
Author(s)
Ananya Sitaram, Peter Elgee, Gretchen K. Campbell, Daniel Barker, Nikolai Klimov, Stephen Eckel
We demonstrate a compact magneto-optical trap (MOT) of alkaline-earth atoms using a nanofabricated diffraction grating chip. A single input laser beam, resonant with the broad 1S0 to 1P1 transition of strontium, forms the MOT in combination with three

On-chip Silicon Photonics Radiation Sensors

September 18, 2019
Author(s)
Nikolai N. Klimov, Zeeshan Ahmed, Lonnie T. Cumberland, Ileana M. Pazos, Ronald E. Tosh, Ryan P. Fitzgerald
We have examined the impact of cobalt-60-ray radiation up to 1 megagray (MGy) absorbed dose on silicon photonic devices. We do not find any systematic impact of radiation on passivated devices, indicating the durability of passivated silicon devices

PHOTONIC THERMOMETRY: UPENDING 100 YEAR-OLD PARADIGM IN TEMPERATURE METROLOGY

August 1, 2019
Author(s)
Zeeshan Ahmed, Nikolai N. Klimov, Thomas P. Purdy, Tobias K. Herman, Kevin O. Douglass, Ryan P. Fitzgerald
For the past century, industrial temperature measurements have relied on resistance measurement of a thin metal wire or thin metal film whose resistance varies with temperature. Today’s resistance thermometers can routinely measure temperatures with

Nuclear-Spin Dependent Parity Violation in Optically Trapped Polyatomic Molecules

July 3, 2019
Author(s)
Eric B. Norrgard, Daniel S. Barker, Stephen P. Eckel, James A. Fedchak, Nikolai N. Klimov, Julia K. Scherschligt
We investigate using optically trapped linear polyatomic molecules as probes of nuclear spin- dependent parity violation. The presence of closely spaced, opposite-parity $\ell$-doublets is a general feature of such molecules, allowing parity-violation

A single-beam slower and magneto-optical trap using a nanofabricated grating

June 11, 2019
Author(s)
Daniel S. Barker, Eric B. Norrgard, Nikolai N. Klimov, James A. Fedchak, Julia K. Scherschligt, Stephen P. Eckel
We demonstrate a compact (0.25 L) system for laser cooling and trapping atoms from a heated dispenser source. Our system uses a nano-fabricated diffraction grating to generate a magneto- optical trap (MOT) using a single input laser beam. An aperture in

Fabrication and Testing of Photonic Thermometers

October 24, 2018
Author(s)
Nikolai Klimov, Zeeshan Ahmed
In recent years, a push for developing novel silicon photonic devices for telecommunications has generated a vast knowledge base that is now being leveraged for developing sophisticated photonic sensors. Silicon photonic sensors seek to exploit the strong

Challenges to miniaturizing cold atom technology for deployable vacuum metrology

September 14, 2018
Author(s)
Stephen P. Eckel, Daniel S. Barker, James A. Fedchak, Nikolai N. Klimov, Eric B. Norrgard, Julia K. Scherschligt, Constantinos Makrides, Eite Tiesinga
Cold atoms are excellent metrological tools; they currently realize SI time and, soon, SI pressure in the ultra-high (UHV) and extreme high vacuum (XHV) regimes. The development of primary, vacuum metrology based on cold atoms currently falls under the

Assessing Radiation Hardness of Silicon Photonic Sensors.

August 13, 2018
Author(s)
Zeeshan Ahmed, Lonnie T. Cumberland, Ronald E. Tosh, Nikolai N. Klimov, Ileana M. Pazos, Ryan P. Fitzgerald
In recent years silicon photonic platforms have undergone rapid maturation enabling not only optical communication but complex scientific experiments ranging from sensors applications to fundamental physics inquiries. There is con-siderable interest in

Recent Developments in Surface Science and Engineering, Thin Films, Nanoscience, Biomaterials, Plasma Science, and Vacuum Technology

May 31, 2018
Author(s)
Miran Mozetic, Alenka Vesel, Gregor Primc, J. Bauer, A. Eder, G. H. S. Schmid, David Ruzic, Zeeshan Ahmed, Daniel Barker, Kevin O. Douglass, Stephen Eckel, James A. Fedchak, Jay H. Hendricks, Nikolai Klimov, Jacob Edmond Ricker, Julia Scherschligt, Jack A. Stone Jr., Gregory F. Strouse, I. Capan, M Buljan, S. Milosevic, C Teichert, S R. Cohen, A G. Silva, M Lehocky, P Humpolicek, C Rodriguez, J Hernandez-Montelongo, E Punzon-Quijorna, D Mercier, M Manso-Silvan, G Ceccone, A Galtayries, K Stana-Kleinschek, I Petrov, J E. Greene, J Avila, C Y. Chen, B Caja, H Yi, A Boury, S Lorcy, M C. Asensio, T Gans, D O?Connell, F Reniers, A Vincze, M Anderle
Nanometer-sized structures, surfaces and sub-surface phenomena have played an enormous role in science and technological applications and represent a driving-force of current interdisciplinary science. Recent developments include the atomic-scale

A 3D-printed alkali metal dispenser

May 1, 2018
Author(s)
Eric B. Norrgard, Daniel S. Barker, James A. Fedchak, Nikolai N. Klimov, Julia K. Scherschligt, Stephen P. Eckel
We demonstrate and characterize a source of Li atoms made from direct metal laser sintered Ti. The source's outgassing rate is measured to be $5 \,(2)\cdot 10^{-7}$\,$\rm{Pa}~ \rm{L}~ \rm{s}^{-1}$ at the temperature which optimizes the number of atoms

Towards Replacing Resistance Thermometry with Photonic Thermometry

December 6, 2017
Author(s)
Nikolai Klimov, Thomas P. Purdy, Zeeshan Ahmed
Resistance thermometry provides a time-tested method for taking temperature measurements that has been painstakingly developed over the last century. However, fundamental limits to resistance-based approaches along with a desire to reduce the cost of

Development of a new UHV/XHV pressure standard (Cold Atom Vacuum Standard)

November 10, 2017
Author(s)
Julia Scherschligt, James A. Fedchak, Daniel Barker, Stephen Eckel, Nikolai Klimov, Constantinos Makrides, Eite Tiesinga
The National Institute of Standards and Technology has recently begun a program to develop a primary pressure standard that is based on ultra-cold atoms, covering a pressure range of 1 × 10-6 Pa to 1 × 10-10 Pa and possibly lower. These pressures

Toward 3D printed hydrogen storage materials made with ABS-MOF composites

September 26, 2017
Author(s)
Megan C. Kreider, Zeeshan Ahmed, Makfir Sefa, James A. Fedchak, Julia Scherschligt, Michael Bible, Nikolai Klimov, Bharath Natarajan, Hartings Mathew
The push to advance efficient, renewable, and clean energy sources has brought with it an effort to generate materials that are capable of storing hydrogen. Metal-organic framework materials (MOFs) have been the focus of many such studies as they are

Coulomb drag and counterflow Seebeck coefficient in bilayer-graphene double layers

July 21, 2017
Author(s)
Jiuning Hu, David B. Newell, Jifa Tian, Nikolai N. Klimov, Tailung Wu, Yong Chen
We have fabricated bilayer-graphene double layers separated by a thin (~20 nm) boron nitride layer and performed Coulomb drag and counterflow thermoelectric transport measurements. The measured Coulomb drag resistivity is nearly three orders smaller in

Impact of Varying Vacuum Levels on Self-Heating in Photonic Thermometers

July 1, 2017
Author(s)
Zeeshan Ahmed, Nikolai N. Klimov, James R. Hands, James A. Fedchak
Here we examine the impact of vacuum levels on self-heating in photonic crystal cavity thermometers. Our results suggest that background gas pressure has a negligible impact on self- heating correction to the temperature-wavelength calibration.