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Search Publications by: John R. Lawall (Fed)

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Displaying 1 - 25 of 46

Coupling an epitaxial quantum dot to a fiber-based external-mirror microcavity

June 3, 2021
Author(s)
Andreas Muller, Edward B. Flagg, Michael Metcalfe, John R. Lawall, Glenn S. Solomon
We report the coupling of individual InAs quantum dots (QDs) to a single mode of an external-mirror optical microcavity. The external mirror is bonded to a fiber and positioned above a semiconductor sample consisting of a QD-containing GaAs layer grown

Heterodyne measurement of resonant elastic scattering from epitaxial quantum dots

June 3, 2021
Author(s)
Michael Metcalfe, Glenn S. Solomon, John Lawall
Resonant elastic scattering from InAs quantum dots (QDs) is studied by heterodyne spectroscopy. We show theoretically that heterodyne spectroscopy of a two-level quantum emitter is not sensitive to the inelastic fluorescence component. In practice, we

Tunable quantum beat of single photons enabled by nonlinear nanophotonics

November 22, 2019
Author(s)
Qing Li, Anshuman Singh, Xiyuan Lu, John Lawall, Varun Verma, Richard Mirin, Sae Woo Nam, Kartik Srinivasan
Integrated photonics is a promising approach for scalable implementation of diverse quantum resources at the chip-scale. Here, we demonstrate the integration of two essential building blocks for quantum information science - quantum sources and frequency

Quantum Frequency Conversion of a Quantum Dot Single-Photon Source on a Nanophotonic Chip

May 20, 2019
Author(s)
Anshuman Singh, Qing Li, Shunfa Liu, Ying Yu, Xiyuan Lu, Christian Schneider, Sven Hofling, John Lawall, Varun Verma, Richard Mirin, Sae Woo Nam, Jin Liu, Kartik Srinivasan
Single self-assembled InAs/GaAs quantum dots are promising bright sources of indistinguishable photons for quantum information science. However, their distribution in emission wavelength, due to inhomogeneous broadening inherent to their growth, has

Single self-assembled InAs/GaAs quantum dots in photonic nanostructures: the role of nanofabrication

June 13, 2018
Author(s)
Jin Liu, Kumarasiri Konthasinghe, Marcelo I. Davanco, John Lawall, Vikas Anant, Varun Verma, Richard Mirin, Jin Dong Song, Ben Ma, Ze Sheng Chen, Hai Qiao Ni, Zhi Chuan Niu, Kartik Srinivasan
Single self-assembled InAs/GaAs quantum dots are a promising solid-state quantum technology, with vacuum Rabi splitting, single-photon-level nonlinearities, and bright, pure, and indistinguishable single-photon generation having been demonstrated. In such

Coupled Bilayer Photonic Crystal Slab Electro-Optic Spatial Light Modulators

March 1, 2017
Author(s)
Yichen Shuai, Deyin Zhao, Corey A. Stambaugh, John R. Lawall, Weidong Zhou, Yonghao Liu
We demonstrate here a surface-normal ultracompact Fano resonance electrooptic spatial light modulator employing a stacked photonic crystal membrane capacitor-like structure. Vertically coupled optical resonance near 1.5 μm was observed, and both blue and

Observation of optomechanical buckling phase transitions

March 1, 2017
Author(s)
Jacob M. Taylor, John R. Lawall, Haitan Xu, Utku Kemiktarak, Jingyun Fan, Stephen Ragole
Correlated phases of matter provide long-term stability for systems as diverse as solids, magnets, and potential exotic quantum materials. Mechanical systems, such as relays and buckling transition spring switches can yield similar stability by exploiting

An Optomechanical Accelerometer with a High-Finesse Hemispherical Optical Cavity

February 22, 2016
Author(s)
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
Author(s)
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

Alignment and testing of the NIST Calculable Capacitor

August 24, 2014
Author(s)
Yicheng Wang, Felipe Guzman, Corey A. Stambaugh, Radek Smid, Hugo Zuniga Calvo, Andrew D. Koffman, Jon R. Pratt, John R. Lawall
This paper reports progress on the NIST effort to develop a new calculable capacitor, focusing on improvement of the guard electrode motion control as well as issues associated with the overall electrode alignment. Design of a multi-wavelength Fabry-Perot

Mode competition and anomalous cooling in a multimode phonon laser

July 15, 2014
Author(s)
Utku Kemiktarak, Michael Metcalfe, Mathieu Durand, John R. Lawall
We study mode competition in a multimode “phonon laser” comprised of a Fabry-Perot cavity employing a highly reflective membrane as the output coupler. Mechanical gain is provided by driving the cavity with a blue-detuned pump laser, and many mechanical

Accurate Gouy phase measurement in an astigmatic optical cavity

September 14, 2012
Author(s)
John R. Lawall, Mathieu Durand, Yicheng Wang
We present measurements of the Gouy phase accumulation for the fundamental mode of an astigmatic Fabry-Perot cavity over 70 % of its stability range. The method is based on simultaneous measurement of the resonant frequencies of the fundamental mode and

Porous Superhydrophobic Membranes: Hydrodynamic Anomaly in Oscillating Flows

October 17, 2011
Author(s)
Sukumar Rajauria, O. Ozsun, John R. Lawall, V. Yakhot, Kamil L. Ekinci
Inspiration for man-made superhydrophobic surfaces comes from Nature: the Lotus leaf [1–3], for instance, exploits superhydrophobicity to keep its surface dry and clean from contaminants. Superhydrophobicity emerges due to roughness on a chemically

High-accuracy Fabry-Perot displacement interferometry using fiber lasers

August 8, 2011
Author(s)
Mathieu Durand, John R. Lawall, Yicheng Wang
We describe ongoing work in a Fabry-Perot interferometry system designed to measure displacements over a range of 50~mm with sub-pm uncertainty. The apparatus involves probing two nearby modes of the Fabry-Perot cavity with narrow-linewidth fiber telecom

Resolved sideband emission from dynamically strained quantum dots

July 16, 2010
Author(s)
Michael Metcalfe, Stephen M. Carr, Andreas Muller, Glenn S. Solomon, John R. Lawall
The dynamic response of InAs/GaAs self-assembled quantum dots (QDs) to strain is studied by periodically modulating the QDs with a surface acoustic wave (SAW) and measuring the QD fluorescence with both photoluminescence and resonant spectroscopy. When the

Ultrahigh finesse low mode volume Fabry-Perot microcavity

July 1, 2010
Author(s)
Andreas Muller, Edward B. Flagg, John R. Lawall, Glenn S. Solomon
Ultralow loss concave micromirrors with radii of curvature below 60 um were fabricated by laser ablation and reflective coatings. A 10 um long microcavity with a mode volume of 40 um^3 was set up with two such mirrors and the cavity linewidth measured both

Fabry-Perot Metrology for Displacements up to 50 mm

October 16, 2008
Author(s)
John R. Lawall
A system designed to apply Fabry-Perot interferometry to the measurement of displacements is described. Two adjacent modes of a Fabry-Perot cavity are probed, and both the absolute optical frequencies and their difference are used to determine

Laser Doppler vibrometer employing active frequency feedback

September 17, 2008
Author(s)
Akobuije D. Chijioke, John R. Lawall
We present a heterodyne Michelson interferometer for vibration measurement in which feedback is used to obviate the need to unwrap phase data. The Doppler shift of a vibrating target mirror is sensed interferometrically and compensated by means of a