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Search Publications by: Thomas W. LeBrun (Fed)

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Displaying 1 - 25 of 31

Low-power, agile electro-optic frequency comb spectrometer for integrated sensors

March 11, 2024
Kyunghun Han, David Long, Sean Bresler, Junyeob Song, Yiliang Bao, Benjamin Reschovsky, Kartik Srinivasan, Jason J. Gorman, Vladimir Aksyuk, Thomas W. LeBrun
Sensing platforms based upon photonic integrated circuits have shown considerable promise; however, they require corresponding advancements in integrated optical readout technologies. Here, we present an on-chip spectrometer that leverages an integrated

Single-modulator, direct frequency comb spectroscopy via serrodyne modulation

February 3, 2023
David Long, Sean Bresler, Yiliang Bao, Benjamin Reschovsky, Thomas W. LeBrun, Jason J. Gorman
Traditional electro-optic frequency comb spectrometers rely upon the use of an acousto-optic modulator (AOM) to provide a differential frequency shift between probe and local oscillator (LO) legs of the interferometer. Here we show that these modulators

Intrinsically accurate sensing with an optomechanical accelerometer

May 18, 2022
Benjamin Reschovsky, David Long, Feng Zhou, Yiliang Bao, Richard A. Allen, Jason J. Gorman, Thomas W. LeBrun
We demonstrate a microfabricated optomechanical accelerometer that is capable of percent-level accuracy without external calibration. To achieve this capability, we use a mechanical model of the device behavior that can be characterized by the thermal

Broadband thermomechanically limited sensing with an optomechanical accelerometer

March 9, 2021
Feng Zhou, Yiliang Bao, Ramgopal Madugani, David Long, Jason J. Gorman, Thomas W. LeBrun
Cavity optomechanics has enabled precision measurements with unprecedented levels of sensitivity, including the detection of attonewton forces, nanoparticles, magnetic fields, and gravitational waves. In most cases, detection is performed in a narrow

Electro-optic frequency combs for rapid interrogation in cavity optomechanics

January 29, 2021
David Long, Benjamin J. Reschovsky, Feng Zhou, Yiliang Bao, Thomas W. LeBrun, Jason Gorman
Electro-optic frequency combs were employed to rapidly interrogate an optomechanical sensor, demonstrating spectral resolution substantially exceeding that possible with a mode-locked frequency comb. Frequency combs were generated using an integrated

A radial calibration window for analytical ultracentrifugation

July 20, 2018
Thomas W. LeBrun, Peter Schuck, Wei Ren, Justine Yoon, Xianghui Dong, Nicole Y. Morgan, Jeffrey Fagan, Huaying Zhao
Analytical ultracentrifugation (AUC) is a first-principles based method for studying particles in solution by monitoring the evolution of their radial concentration distribution as a function of time in the presence of a high centrifugal field. In

A Photonic MEMS Accelerometer with a Low-Finesse Hemispherical Microcavity Readout

August 13, 2017
Yiliang Bao, Feng Zhou, Thomas W. LeBrun, Jason J. Gorman
This paper describes the design, fabrication, and testing of a photonic MEMS accelerometer that uses a hemispherical microcavity to transduce the motion of the proof mass. The cavity design provides stable operation that is relatively tolerant of

Concave silicon micromirrors for stable hemispherical optical microcavities

June 23, 2017
Yiliang Bao, Feng Zhou, Thomas W. LeBrun, Jason J. Gorman
A detailed study of the fabrication of silicon concave micromirrors for hemispherical microcavities is presented that includes fabrication yield, surface quality, surface roughness, cavity depth, radius of curvature, and the aspect ratio between the cavity

An Optomechanical Accelerometer with a High-Finesse Hemispherical Optical Cavity

February 22, 2016
Yiliang Bao, Felipe Guzman, Arvind Balijepalli, John Lawall, Jacob Taylor, Thomas W. LeBrun, Jason J. Gorman
A new design for an optomechanical accelerometer is presented. The design includes a hemispherical optical cavity that can achieve high finesse and a proof mass that is well-constrained by silicon nitride beams. Based on previous work and analysis, the

MEMS optomechanical accelerometry standards

July 8, 2015
Felipe Guzman, Yiliang Bao, Jason J. Gorman, John R. Lawall, Jacob M. Taylor, Thomas W. LeBrun
Current acceleration primary standards reach relative uncertainties of the order of 0.001 and consist of complex test facilities, typically operated at National Metrology Institutes. Our research focuses on the development of silicon mechanical oscillator

Feedback Control of Optically Trapped Particles

December 17, 2011
Jason J. Gorman, Arvind K. Balijepalli, Thomas W. LeBrun
Optical trapping is a method for manipulating micro- and nanoscale particles that is widely used in biophysics and colloid science, among other areas. This method uses optical forces to confine the position of a particle to a localized region, which is

A Flexible System Framework for a Nanoassembly Cell Using Optical Tweezers

January 1, 2006
Arvind K. Balijepalli, Thomas W. LeBrun, Satyandra K. Gupta
The optical tweezers instrument is a unique tool for directed assembly of nanocomponents. In order to function as a viable nanomanufacturing tool, a software architecture is needed to run the optical tweezers hardware, provide an effective user interface

Three-dimensional Scanning Optical Tweezers

December 5, 2005
Thomas W. LeBrun, T W. Hwang, I Y. Park, Jun-Feng Song, Yong-Gu Lee, Nicholas G. Dagalakis, Cedric V. Gagnon, Arvind K. Balijepalli
There are several new tools for manipulating microscopic objects. Among them, optical tweezers (OT) has two distinguishing advantages. Firstly, OT can easily release an object without the need of a complicated detaching scheme. Secondly, it is anticipated

A Modular System Architecture for Agile Assembly of Nanocomponents using Optical Tweezers

September 10, 2005
Arvind K. Balijepalli, Thomas W. LeBrun, Cedric V. Gagnon, Yong-Gu Lee, Nicholas G. Dagalakis
In order to realize the flexibility optical trapping offers as a nanoassembly tool, we need to develop natural and intuitiveinterfaces to assemble large quantities of nanocomponents quickly and cheaply. We propose a system to create such aninterface that

Characterization of Optical Traps Using On-Line Estimation Methods

August 26, 2005
Jason J. Gorman, Thomas W. LeBrun, et al
System identification methods are presented for the estimation of the characteristic frequency of an optically trapped particle. These methods are more amenable to automated on-line measurements and are believed to be less prone to erroneous results

Development of Multiple Beam Optical Tweezers

June 1, 2005
Dongjin Lee, Thomas W. LeBrun, Arvind Balijepalli, Jason J. Gorman, Cedric V. Gagnon, Daehie Hong, Esther H. Chang
This paper presents the design of a multiple beam optical tweezers instrument used for manipulating micro/nano-sized components. The basic equations used in designing the optical tweezers are derived and the stable and time-sharing multiple beam optical