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Search Publications by: Samuel Berweger (Fed)

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Displaying 1 - 25 of 31

Zeeman-resolved Autler-Townes splitting in Rydberg atoms with a tunable RF resonance and a single transition dipole moment

February 21, 2024
Author(s)
Noah Schlossberger, Drew Rotunno, Aly Artusio-Glimpse, Nik Prajapati, Samuel Berweger, Dangka Shylla, Matt Simons, Christopher L. Holloway
Applying a magnetic field as a method for tuning the frequency of Autler-Townes splitting for Rydberg electrometry has recently been demonstrated. In this Letter, we provide a theoretical understanding of Rydberg electromechanically-induced-transparency

Towards Opportunistic Radar Sensing Using Millimeter-wave WiFi

January 1, 2024
Author(s)
Jian Wang, Jack Chuang, Samuel Berweger, Camillo Gentile, Nada T. Golmie
Sensing with communication waveforms has drawn growing interest thanks to the ubiquitous availability of wireless networks. However, the required sensing resources may not always be available in a communication system. In addition, the communication system

Adaptive Channel-State-Information Feedback in Integrated Sensing and Communication Systems

August 28, 2023
Author(s)
Neeraj Varshney, Samuel Berweger, Jack Chuang, Steve Blandino, Jian Wang, Neha Pazare, Camillo Gentile, Nada T. Golmie
Efficient design of integrated sensing and communication systems can minimize signaling overhead by reducing the size and/or rate of feedback in reporting channel state information (CSI). To minimize the signaling overhead when performing sensing

Investigating electromagnetically induced transparency spectral lineshape distortion due to non-uniform fields in Rydberg-atom electrometry

August 25, 2023
Author(s)
Drew Rotunno, Samuel Berweger, Nik Prajapati, Aly Artusio-Glimpse, MATTHEW SIMONS, chris holloway, Amy Robinson
We investigate the effects of spatially non-uniform radio-frequency electric (E) field amplitudes on the spectral line shapes of electromagnetically induced transparency (EIT) signals in Rydberg atomic systems used in electrometry (i.e., the metrology of E

Synthetic Aperture RF Reception using Rydberg Atoms

August 2, 2023
Author(s)
Nik Prajapati, Aly Artusio-Glimpse, Matt Simons, Samuel Berweger, Drew Rotunno, Maitreyi Jayaseelan, Kaleb Campbell, Christopher L. Holloway
Rydberg atoms show great promise for use as self-calibrated electric field sensors for a broad range of frequencies. Their response is traceable to the international system of units making them a valuable tool for a variety of applications including

Inverse Transform Sampling for Efficient Doppler-Averaged Spectroscopy Simulations

July 14, 2023
Author(s)
Drew Rotunno, Nik Prajapati, Samuel Berweger, MATTHEW SIMONS, Aly Artusio-Glimpse, Amy Robinson, chris holloway
We present a thermal velocity sampling method for calculating Doppler-broadened atomic spectra, which more efficiently reaches a smooth limit than regular velocity weighted sampling. The method uses equal-population sampling of the 1-D thermal distribution

Rydberg Atoms for One-Step Traceability for Sensing Electric Fields

May 8, 2023
Author(s)
Aly Artusio-Glimpse, Christopher L. Holloway, Matt Simons, Nik Prajapati, Drew Rotunno, Samuel Berweger, Kaleb Campbell, Maitreyi Jayaseelan
Absolute electric field measurements present a "chicken-and-egg" situation where calibration of field probes relies on accurate knowledge of the field while precise determination of the field involves measurements with a calibrated probe. Metrology

Rydberg Engineering: Recent Techniques for Sensitive Field Measurements

February 9, 2023
Author(s)
Drew Rotunno, Nik Prajapati, Samuel Berweger, Aly Artusio-Glimpse, MATTHEW SIMONS, chris holloway, Amy Robinson
Highly-excited Rydberg atoms have been used for International System of Unit (SI)-traceable radio-frequency (RF) electric field and power measurements, but are limited in sensitivity to order 100 $\mu$V/m/$\sqrtHz}$ by noise and linewidth issues. These

Quantum phase modulation with acoustic cavities and quantum dots

April 29, 2022
Author(s)
Poolad Imany, Zixuan Wang, Ryan DeCrescent, Robert Boutelle, Corey McDonald, Travis Autry, Samuel Berweger, Pavel Kabos, Sae Woo Nam, Richard Mirin, Kevin L. Silverman
Fast, efficient, and low-power modulation of light at microwave frequencies is crucial for chip-scale classical and quantum processing as well as for long-range networks of superconducting quantum processors. A successful approach to bridge the gap between

Nanoscale Photoexcited Carrier Dynamics in Perovskites

March 8, 2022
Author(s)
Samuel Berweger, Fei Zhang, Bryon Larson, Andrew Ferguson, Axel Palmstrom, Obadiah Reid, Thomas Mitchell (Mitch) Wallis, Kai Zhu, Joseph Berry, Pavel Kabos, Sanjini Nanayakkara
The excellent optoelectronic properties of lead-halide perovskite thin films are complemented by their tolerance to broad compositional variations and associated strain, which allows tuning of desired properties such as the optical bandgap. On the other

Perspectives in Scanning Probe Microscopy from the 2021 Joint International Scanning Probe Microscopy and Scanning Probe Microscopy on Soft and Polymeric Materials Conference

November 30, 2021
Author(s)
Liam Collins, Jason Killgore, Samuel Berweger, Rachael Cohn, neus domingo, Georg Fantner, Rajiv Giridharagopal, Sergei Kalinin, Philippe LECLERE, Simon Scheuring, Rama Vasudevan, Dalia Yablon
In March 2020 our plans for organizing and hosting one of the premier scanning probe microscopy (SPM) conferences in Breckenridge, Colorado, USA were well underway. For the first time the meeting would synergistically combine International Scanning Probe

Imaging of Magnetic Excitations in Nanostructures with Microwave Near-Field Microscopy

November 25, 2021
Author(s)
Samuel Berweger, Robert Tyrrell-Ead, Houchen Chang, Mingzhong Wu, Hong Tang, Hans Nembach, Karl Stupic, Stephen E. Russek, Thomas Mitchell (Mitch) Wallis, Pavel Kabos
We present images of spin-wave excitations in a patterned yttrium iron garnet (YIG) thin film obtained by use of near-field microwave microscopy, which can achieve spatial resolution as high as 50 nm. Visualization of magnetic excitations is an enticing

Enhancement of electromagnetically induced transparency based Rydberg-atom electrometry through population repumping

November 22, 2021
Author(s)
chris holloway, Nik Prajapati, MATTHEW SIMONS, Samuel Berweger, Aly Artusio-Glimpse, Amy Robinson
We demonstrate the improvement of Rydberg electrometry based on electromagnetically induced transparency (EIT) through the use of a ground state repumping laser. Though there are many factors that limit the sensitivity of radio frequency field measurements

Spatially Resolved Photoconductivity in WS2/MoS2 lateral heterostructures

April 27, 2021
Author(s)
Samuel Berweger, Hanyu Zhang, Prasana Sahoo, Benjamin Kupp, Jeffrey Blackburn, Elisa Miller, Thomas Mitchell (Mitch) Wallis, Dmitri Voronine, Pavel Kabos, Sanjini Nanayakkara
The optical and electronic properties of 2D semiconductors are intrinsically linked via the strong interactions between optically excited bound species and free carriers. Here we use near-field scanning microwave microscopy (SMM) to image spatial

Substrate-enhanced photothermal nano-imaging of surface polaritons in monolayer graphene

April 1, 2021
Author(s)
Samuel Berweger, Fabian Menges, Honghua Yang, Tao Jiang, Markus B. Raschke
Surface polaritons comprise a wealth of light-matter interactions with deep subwavelength scale confinement of electromagnetic modes. However, their nanoscale localized dissipation and thermalization processes are not readably accessible experimentally

Microscopic Origin of Inhomogeneous Transport in Four-Terminal Tellurene Devices

December 22, 2020
Author(s)
Benjamin Kupp, Gang Qiu, Yixiu Wang, Clayton Caspeer, Thomas Mitchell (Mitch) Wallis, Joanna Atkin, Wenzhuo Wu, Peide Ye, Pavel Kabos, Samuel Berweger
Tellurene—the 2D form of elemental tellurium—provides an attractive alternative to conventional 2D semiconductors due to its high bipolar mobilities, facile solution processing, and the possibility of dopant intercalation into its 1D van der Waals lattice

Crystallographic Polarity Measurements in Two-Terminal GaN Nanowire Devices by Lateral Piezoresponse Force Microscopy

July 23, 2020
Author(s)
Matthew Brubaker, Alexana Roshko, Samuel Berweger, Paul T. Blanchard, Todd E. Harvey, Norman A. Sanford, Kris A. Bertness
Lateral piezoresponse force microscopy (L-PFM) is demonstrated as a reliable method for determining the crystallographic polarity of individual, dispersed GaN nanowires that were functional components in electrical test structures. In contrast to PFM

Imaging Carrier Inhomogeneities in Ambipolar Tellurene Field Effect Transistors

February 12, 2020
Author(s)
Samuel Berweger, Gang Qiu, Yixiu Wang, Benjamin Pollard, Kristen Genter, Thomas Mitchell (Mitch) Wallis, Wenzhuo Wu, Peide Ye, Pavel Kabos
Bipolar transport underpins a wide range of semiconductor homojunction device functionalities such as pn junctions or transistors. The capability to image and understand spatial inhomogeneities un carrier type and the conductivity associated with each

Design of an intelligent PYTHON code to run coupled and license-free finite-element and statistical analysis software for calibration of near-field scanning microwave microscopes

October 2, 2019
Author(s)
Jeffrey T. Fong, N. Alan Heckert, James Filliben, Pedro V. Marcal, Samuel Berweger, Thomas Mitchell (Mitch) Wallis, Pavel Kabos
To calibrate near-field scanning microwave microscopes (NSMM) for defect detection and characterization in semiconductors, it is common to develop a parametric finite element analysis (FEA) code to guide the microscope user on how to optimize the settings

Methylammonium lead iodide grain boundaries exhibit depth-dependent electrical properties

September 23, 2016
Author(s)
Gordon A. MacDonald, Mengjin Yang, Samuel Berweger, Jason Killgore, Pavel Kabos, Joeseph Berry, Kai Zhu, Frank W. DelRio
In this letter, the nanoscale through-film and lateral photoresponse and conductivity of large-grained methylammonium lead iodide thin films are studied. In perovskite solar cells (PSC), these films result in efficiencies > 17%. The top surface of the