956 citations · 3k across the 26 of their papers we have counts for
27 papers
Free-Standing Epitaxial SrTiO Nanomembranes via Remote Epitaxy using Hybrid Molecular Beam Epitaxy
Hyojin Yoon, Tristan K. Truttmann, Fengdeng Liu +12
The epitaxial growth of functional materials using a substrate with a graphene layer is a highly desirable method for improving structural quality and obtaining free-standing epita…
How to Report and Benchmark Emerging Field-Effect Transistors
Zhihui Cheng, Chin-Sheng Pang, Peiqi Wang +13
Emerging low-dimensional nanomaterials have been studied for decades in device applications as field-effect transistors (FETs). However, properly reporting and comparing device per…
Supervised Learning in Temporally-Coded Spiking Neural Networks with Approximate Backpropagation
Andrew Stephan, Brian Gardner, Steven J. Koester +1
In this work we propose a new supervised learning method for temporally-encoded multilayer spiking networks to perform classification. The method employs a reinforcement signal tha…
Spin-Hall MTJ Cells for Intra-Column Competition in Hierarchical Temporal Memory
Andrew W. Stephan, Steven J. Koester
We propose a dedicated winner-take-all circuit to efficiently implement the intra-column competition between cells in Hierarchical Temporal Memory which is a crucial part of the al…
SHE-MTJ Circuits for Convolutional Neural Networks
Andrew W. Stephan, Steven J. Koester
We report the performance characteristics of a notional Convolutional Neural Network based on the previously-proposed Multiply-Accumulate-Activate-Pool set, an MTJ-based spintronic…
Layer-dependence of dielectric response and water-enhanced ambient degradation of highly-anisotropic black As
Hwanhui Yun, Supriya Ghosh, Prafful Golani +2
Black arsenic (BAs) is a van der Waals layered material with a puckered honeycomb structure and has received increased interest due to its anisotropic properties and promising perf…
Nonvolatile Spintronic Memory Cells for Neural Networks
Andrew W. Stephan, Qiuwen Lou, Michael Niemier +2
A new spintronic nonvolatile memory cell analogous to 1T DRAM with non-destructive read is proposed. The cells can be used as neural computing units. A dual-circuit neural network…
Convolutional Neural Networks Utilizing Multifunctional Spin-Hall MTJ Neurons
Andrew W. Stephan, Steven J. Koester
We propose a new network architecture for standard spin-Hall magnetic tunnel junction-based spintronic neurons that allows them to compute multiple critical convolutional neural ne…
Benchmarking Inverse Rashba-Edelstein Magnetoelectric Devices for Neuromorphic Computing
Andrew W. Stephan, Jiaxi Hu, Steven J. Koester
We propose a new design for a cellular neural network with spintronic neurons and CMOS-based synapses. Harnessing the magnetoelectric and inverse Rashba-Edelstein effects allows na…
An analytic virtual-source-based current-voltage model for ultra-thin black phosphorus field-effect transistors
Elahe Yarmoghaddam, Nazila Haratipour, Steven J. Koester +1
In this paper, we develop an analytic physics-based model to describe current conduction in ultra-thin black phosphorus (BP) field-effect transistors (FETs). The model extends the…
An Inside Look at the Ti-MoS2 Contact in Ultra-thin Field Effect Transistor with Atomic Resolution
Ryan J. Wu, Sagar Udyavara, Rui Ma +5
Two-dimensional molybdenum disulfide (MoS2) is an excellent channel material for ultra-thin field effect transistors. However, high contact resistance across the metal-MoS2 interfa…
Spin absorption by in situ deposited nanoscale magnets on graphene spin valves
Walid Amamou, Gordon Stecklein, Steven J. Koester +2
An in situ measurement of spin transport in a graphene nonlocal spin valve is used to quantify the spin current absorbed by a small (250 nm 750 nm) metallic island. The ex…
Using Programmable Graphene Channels as Weights in Spin-Diffusive Neuromorphic Computing
Jiaxi Hu, Gordon Stecklein, Yoska Anugrah +2
A graphene-based spin-diffusive (GrSD) neural network is presented in this work that takes advantage of the locally tunable spin transport of graphene and the non-volatility of nan…
Semi-analytical model of the contact resistance in two-dimensional semiconductors
Roberto Grassi, Yanqing Wu, Steven J. Koester +1
Contact resistance is a severe performance bottleneck for electronic devices based on two-dimensional layered (2D) semiconductors, whose contacts are Schottky rather than Ohmic. Al…
Efficient Electrical Control of Thin-Film Black Phosphorus Bandgap
Bingchen Deng, Vy Tran, Hao Jiang +10
Recently rediscovered black phosphorus is a layered semiconductor with promising electronic and photonic properties. Dynamic control of its bandgap can enable novel device applicat…
Band Alignment of 2D Semiconductors for Designing Heterostructures with Momentum Space Matching
V. Ongun Özçelik, Javad G. Azadani, Ce Yang +2
We present a comprehensive study of the band alignments of two-dimensional (2D) semiconducting materials and highlight the possibilities of forming momentum-matched type I, II and…
Capacitive Sensing of Intercalated H2O Molecules Using Graphene
Eric J. Olson, Rui Ma, Tao Sun +5
Understanding the interactions of ambient molecules with graphene and adjacent dielectrics is of fundamental importance for a range of graphene-based devices, particularly sensors,…
Ambipolar Black Phosphorus MOSFETs with Record n-Channel Transconductance
Nazila Haratipour, Steven J. Koester
Ambipolar black phosphorus MOSFETs with record n-channel extrinsic transconductance are reported. The devices consist of multi-layer black phosphorus aligned to a local back-gate e…
Symmetric Complementary Logic Inverter Using Integrated Black Phosphorus and MoS2 Transistors
Yang Su, Chaitanya U. Kshirsagar, Matthew C. Robbins +2
The operation of an integrated two-dimensional complementary metal-oxide-semiconductor inverter with well-matched input/output voltages is reported. The circuit combines a few-laye…
Black Phosphorus p-MOSFETs with High Transconductance and Nearly Ideal Subthreshold Slope
Nazila Haratipour, Matthew C. Robbins, Steven J. Koester
We report record performance for black phosphorus p-MOSFETs. The devices have locally patterned back gates and 20-nm-thick HfO2 gate dielectrics. Devices with effective gate length…
Waveguide-integrated black phosphorus photodetector with high responsivity and low dark current
Nathan Youngblood, Che Chen, Steven J. Koester +1
Layered two-dimensional materials have shown novel optoelectronic properties and are well suited to be integrated in planar photonic circuits. For example, graphene has been utiliz…
Multifunctional graphene optical modulator and photodetector integrated on silicon waveguides
Nathan Youngblood, Yoska Anugrah, Rui Ma +2
For optical communication, information is converted between optical and electrical signal domains at a high rate. The devices to achieve such a conversion are various types of elec…
Graphene-based quantum capacitance wireless vapor sensors
David A. Deen, Eric J. Olson, Mona A. Ebrish +1
A wireless vapor sensor based upon the quantum capacitance effect in graphene is demonstrated. The sensor consists of a metal-oxide-graphene variable capacitor (varactor) coupled t…
Optical absorption in graphene integrated on silicon waveguides
Huan Li, Yoska Anugrah, Steven J. Koester +1
To fully utilize graphene's remarkable optical properties for optoelectronic applications, it needs to be integrated in planar photonic systems. Here, we demonstrate integration of…