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Search Publications by: Zeeshan Ahmed (Fed)

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Displaying 26 - 50 of 94

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

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

Quantum-based vacuum metrology at NIST

June 20, 2018
Author(s)
Julia K. Scherschligt, James A. Fedchak, Zeeshan Ahmed, Daniel S. Barker, Kevin O. Douglass, Stephen P. Eckel, Edward T. Hanson, Jay H. Hendricks, Thomas P. Purdy, Jacob E. Ricker, Robinjeet Singh
The measurement science in realizing and disseminating the SI unit for pressure, the pascal (Pa), has been the subject of much interest at NIST. Modern optical-based techniques for pascal metrology have been investigated, including multi-photon ionization

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

3D printed ABS-MOF composite materials and their gas storage properties

March 19, 2018
Author(s)
Michael Bible, Makfir Sefa, Julia Scherschligt, Zeeshan Ahmed, James A. Fedchak, Hartings Mathew
Metal organic framework materials (MOFs) have been primarily recognized for their ability to promote selective storage of gas molecules. In their as-synthesized (powdered) form, MOFs are not easily processed for use in end-devices where their properties

Towards Traceable Transient Pressure Metrology

March 13, 2018
Author(s)
Douglas A. Olson, Haijun Liu, Zeeshan Ahmed, Kevin O. Douglass
Here we detail our progress in developing the infrastructure for traceable transient measurements of pressure and temperature. Towards that end, we have built and characterized a dual diaphragm shock tube that allows us to achieve shock amplitude

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

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

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.

Optomechanical Quantum Correlations

May 18, 2017
Author(s)
Thomas P. Purdy, Karen E. Grutter, Kartik A. Srinivasan, Nikolai N. Klimov, Zeeshan Ahmed, Jacob M. Taylor
We present methods to measure optical quantum correlations arising from an optomechanical interaction even when large classical noise sources are present. We demonstrate quantum- backaction-noise-calibrated Brownian motion thermometry as a metrological

Chip-Packaged Silicon Photonic Nanoscale Thermometers

November 30, 2016
Author(s)
Nikolai Klimov, Thomas P. Purdy, Zeeshan Ahmed
We report on the development of on-chip integrated packaged nanoscale silicon photonic themperature sensors capable to detect temperature difference as small as 70 µK, thus showing the potential to replace legacy-based resistance thermometers

Ring Resonator Thermometry

October 31, 2016
Author(s)
Nikolai Klimov, Zeeshan Ahmed
We report on our study of a temperature response of ring resonator based sensors and their interchangeability over a wide temperature range. Our results suggest that with a proper fabrication process control the interchangeability in photonic thermometers