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Search Publications by: Jason Ryan (Fed)

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Displaying 1 - 25 of 124

Sampling from exponential distributions in the time domain with superparamagnetic tunnel junctions

April 22, 2025
Author(s)
Temitayo Adeyeye, Sidra Gibeault, Daniel Lathrop, Matthew Daniels, Mark Stiles, Jabez McClelland, William Borders, Jason Ryan, Philippe Talatchian, Ursula Ebels, Advait Madhavan
Though exponential distributions are ubiquitous in statistical physics and related computational models, sampling them from device behavior is rarely done. The superparamagnetic tunnel junction (SMTJ), a key device in probabilistic computing, shows

Spectroscopy of photoionization from the 1E singlet state in nitrogen-vacancy centers in diamond

October 17, 2024
Author(s)
Sean Blakley, Thuc Mai, Stephen Moxim, Jason Ryan, Adam Biacchi, Angela Hight Walker, Robert McMichael
The 1E—1A1 singlet manifold of the negatively charged nitrogen vacancy (NV −) center in diamond plays a central role in the quantum information and quantum sensing applications of the NV − center. However, the energy of this manifold within the diamond

Continuum of Spin Excitations in the Exactly Solvable Triangular-Lattice Spin Liquid CeMgAl11O19

August 28, 2024
Author(s)
Bin Gao, Tong Chen, Chunxaio Liu, Mason Klemm, Shu Zhang, Zhen Ma, Xianghan Xu, CHOONGJAE WON, Dongzhe Dai, Gregory McCandless, Maiko Kofu, Naoki Murai, Stephen Moxim, Jason Ryan, Xiaozhou Huang, Xiaoping Wang, Julia Chan, Shiyan Li, Sang-Wook Cheong, Oleg Tchernyshyov, Leon Balents, Pengcheng Dai
In magnetically ordered insulators, elementary quasiparticles manifest as spin waves - collective motions of localized magnetic moments that propagate through the lattice - observed via inelastic neutron scattering. In effective spin- 1/2 systems where

Tunable zero-field magnetoresistance responses in Si transistors: Origins and applications

April 16, 2024
Author(s)
Stephen Moxim, Nicholas Harmon, Kenneth Myers, James P Ashton, Elias Frantz, Michael Flatte, Patrick Lenahan, Jason Ryan
The near-zero-field magnetoresistance (NZFMR) response has proven to be a useful tool for studying atomic-scale, paramagnetic defects that are relevant to the reliability of semiconductor devices. The measurement is simple to make and, in some cases

Programmable electrical coupling between stochastic magnetic tunnel junctions

March 29, 2024
Author(s)
Sidra Gibeault, Temitayo Adeyeye, Liam Pocher, Daniel Lathrop, Matthew Daniels, Mark Stiles, Jabez J. McClelland, William Borders, Jason Ryan, Philippe Talatchian, Ursula Ebels, Advait Madhavan
Superparamagnetic tunnel junctions (SMTJs) are promising sources of randomness for compact and energy efficient implementations of various probabilistic computing techniques. When augmented with electronic circuits, the random telegraph fluctuations of the

Intermediate spin pair relaxation through modulation of isotropic hyperfine interaction in frequency-swept spin-dependent recombination in 4H-SiC

February 7, 2022
Author(s)
James Ashton, Brian Manning, Stephen Moxim, Fedor Sharov, Patrick Lenahan, Jason Ryan
Electrically detected magnetic resonance (EDMR) measurements have been extended to sub-mT measurements through utilization of frequency sweeping of the oscillating magnetic field, where conventional electron paramagnetic resonance-based measurements

Detection of individual spin species via frequency-modulated charge pumping

February 2, 2022
Author(s)
James Ashton, Mark Anders, Jason Ryan
We utilize the recently developed frequency-modulated charge pumping technique to detect a single charge per cycle, which strongly suggests a single Si/SiO2 interface trap. This demonstration in sub-micron MOSFETs, in which scaling of the gate oxide yields

Model for the Bipolar Amplification Effect

December 10, 2021
Author(s)
James Ashton, Stephen Moxim, Ashton Purcell, Patrick Lenahan, Jason Ryan
We present a model based on Fitzgerald-Grove surface recombination for the bipolar amplification effect (BAE) measurement, which is widely utilized in electrically detected magnetic resonance (EDMR) to measure reliability and performance-limiting interface

Nonresonant transmission line probe for sensitive interferometric electron spin resonance detection

August 5, 2019
Author(s)
Pragya R. Shrestha, Nandita S. Abhyankar, Mark A. Anders, Kin P. Cheung, Robert M. Gougelet, Jason T. Ryan, Veronika A. Szalai, Jason P. Campbell
Electron spin resonance (ESR) spectroscopy measures paramagnetic free radicals, or electron spins, in a variety of biological, chemical, and physical systems. Detection of diverse paramagnetic species is important in applications ranging from quantum

Slow- and rapid-scan frequency-swept electrically detected magnetic resonance of MOSFETs with a non-resonant microwave probe within a semiconductor wafer-probing station

January 14, 2019
Author(s)
Duane J. McCrory, Mark Anders, Jason Ryan, Pragya Shrestha, Kin P. Cheung, Patrick M. Lenahan, Jason Campbell
We report on a novel electron paramagnetic resonance (EPR) technique that merges electrically detected magnetic resonance (EDMR) with a conventional semiconductor wafer probing station. This union, which we refer to as wafer-level EDMR (WL-EDMR), allows

Parasitic engineering for RRAM control

October 15, 2018
Author(s)
Pragya R. Shrestha, David M. Nminibapiel, Dmitry Veksler, Jason P. Campbell, Jason T. Ryan, helmut Baumgart, Kin P. Cheung
The inevitable current overshoot which follows forming or switching of filamentary resistive random access memory (RRAM) devices is often perceived as a source of variability that should be minimized. This sentiment has resulted in efforts to curtail the