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Search Publications by: Zeeshan Ahmed (Fed)

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Displaying 26 - 48 of 48

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

Gas Uptake of 3-D Printed Acrylonitrile Butadiene Styrene (ABS) Using a Vacuum Apparatus Designed for Absorption and Desorption Studies

October 25, 2016
Author(s)
Makfir Sefa, Zeeshan Ahmed, James A. Fedchak, Nikolai Klimov, Julia Scherschligt
We describe a vacuum apparatus for determining the outgassing rate into vacuum, the diffusion coefficient, and the amount of gas absorbed for various materials. The diffusion coefficient is determined from a model applied to time-dependent desorption data

Thermometry with Optomechanical Cavities

June 6, 2016
Author(s)
Thomas P. Purdy, Karen E. Grutter, Kartik Srinivasan, Nikolai Klimov, Zeeshan Ahmed, Jacob Taylor
Thermally-driven motion of a nanomechanical resonator may be employed as an absolute thermometer. We experimentally measure radiation pressure shot noise induced quantum correlations to absolutely calibrate the motional signal transduced onto an optical

Fiber Bragg Grating Based Thermometry

October 1, 2015
Author(s)
Zeeshan Ahmed, Bernard J. Filla, William F. Guthrie, John S. Quintavalle
In recent years there has been considerable interest in developing photonic temperature sensors such as the Fiber Bragg gratings (FBG) as an alternative to resistance thermometry. In this study we examine the thermal response of FBGs over the temperature

On-Chip Integrated Silicon Photonic Thermometers

September 1, 2015
Author(s)
Nikolai N. Klimov, Thomas P. Purdy, Zeeshan Ahmed
The fundamental limitations of resistance-based thermometry and the desire to reduce sensor ownership have produced considerable interest in the development of photonics-based temperature sensors as an alternative to resistance thermometers. Photonic

Towards Reproducible Ring Resonator Based Temperature Sensors

September 1, 2015
Author(s)
Nikolai Klimov, Michaela Berger, Zeeshan Ahmed
In recent years photonic devices have emerged as a powerful tool for developing novel, high-sensitivity sensors. In particular, tremendous progress has been reported in developing photonic temperature sensors using a wide variety of materials including

On-Chip Silicon Waveguide Bragg Grating Photonic Temperature Sensor

August 4, 2015
Author(s)
Nikolai Klimov, Sunil Mittal, Zeeshan Ahmed, Michaela Berger
Resistance thermometry is a time-tested method for temperature measurements. Fundamental limits to resistance-based approaches, spurred our interest in developing photonic temperature sensors as a viable alternative. In this study we demonstrate that our

Developing Microwave Photonic Temperature Sensors

July 9, 2015
Author(s)
John S. Quintavalle, James Filla, Gregory F. Strouse, Zeeshan Ahmed
In recent years there has been considerable interest in exploiting the temperature dependence of sapphire whispering gallery mode frequency to develop a mechanically stable, high accuracy temperature sensor. Disk-resonator-based devices have been

Fiber Bragg Gratings Embedded in 3D-Printed Scaffolds

June 1, 2015
Author(s)
Peter Liacouras, Khazar Choudhry, Grant Grant, Gregory F. Strouse, Zeeshan Ahmed
In recent years there has been considerable interest in utilizing fiber optic based sensors as embedded sensor for fabricating smart materials. One of the primary motivations is to provide real-time information on the structural health of the material so

Nurturing a Disruptive Technology for Thermodynamic Metrology

September 12, 2014
Author(s)
Zeeshan Ahmed
This presenation lays out a case, based on economic and technologic considerations, that the present technologies for temperature and pressure measurement are ripe for disruption. We argue that a better use of research funds is to identify and nuture

Ultra-Sensitive Chip-Based Photonic Temperature Sensor Using Ring Resonator Structures

February 3, 2014
Author(s)
Haitan Xu, Mohammad Hafezi, Jingyun Fan, Jacob Taylor, Gregory F. Strouse, Zeeshan Ahmed
Temperature is one of the most measured quantity in the world, second only to time. Recently there has been considerable interest in developing photonic temperature sensors to leverage advancements in frequency metrology. Here we show that Silicon based

State Resolved THz Spectroscopy and Dynamics of Crystalline Peptide/Water Systems

July 11, 2011
Author(s)
Zeeshan Ahmed, Shin G. Chou, Karen M. Siegrist, David F. Plusquellic
State resolved THz studies of crystalline peptides and their hydrates have provided precise measures of the infrared active phonon modes that reflect motions on the longest possible length scales in these systems. The impact of co-crystallized water on the

Far Infrared Characterization of Single and Double Walled Carbon Nanotubes

January 17, 2011
Author(s)
Shin G. Chou, Zeeshan Ahmed, Georgy Samsonidze, Jing Kong, Mildred Dresselhaus
Variable temperature high resolution far infrared absorption measurements were carried out for single walled carbon nanotubes samples with different diameter distributions. At a temperature where kBT is significantly lower than the phonon energy, the broad