
Course on Beyond CMOS Computing
06 Jun 2013  Teaching Materials  Contributor(s): Dmitri Nikonov
Complementary metaloxidesemiconductor (CMOS) field effect transistors (FET) underpinned the development of electronics and information technology for the last 30 years. In an amazing saga of development, the semiconductor industry (with a leading role of Intel) has shrunk the size of these transistors from 1000nm to 22nm. As this size approaches atomic limits, the research community is under pressure to find devices which complement CMOS and enable further improvement of performance of …

Uniform Methodology of Benchmarking BeyondCMOS Devices
31 Oct 2012  Online Presentations  Contributor(s): Dmitri Nikonov
Multiple logic devices are presently under study within the Nanoelectronic Research Initiative (NRI) to carry the development of integrated circuits beyond the CMOS roadmap. Structure and operational principles of these devices are described. Theories used for benchmarking these devices are overviewed, and a general methodology is described for consistent estimates of the circuit area, switching time and energy. The results of the comparison of the NRI logic devices using these benchmarks are presented. The promising devices  tunneling FET and spin wave devices  were predicted to perform > 1015 Integer Ops/s/cm2 with power < 1W/cm2.

Performance of Magnetic Quantum Cellular Automata and Limitations due to Thermal Noise
02 Jun 2011  Papers  Contributor(s): Ajey Jacob, Dmitri Nikonov
Operation parameters of magnetic quantum cellular automata are evaluated for the purposes of
reliable logic operation. The dynamics if nanomagnets is simulated via LandauLifshitzGilbert equations with stochastic magnetic field corresponding to thermal fluctuations. It is found that in the macrospin approximation the switching speed does not change under scaling of both size and distances between nanomagnets. Thermal fluctuations put a limitation on the size of nanomagnets, since the gate …

Surface scattering: Made simple
03 Sep 2010  Papers  Contributor(s): Dmitri Nikonov, Himadri Pal
Surface scattering in a quantum well.

Comparisons of macrospin and OOMMF simulations
26 Jan 2010  Presentation Materials  Contributor(s): Dmitri Nikonov, George Bourianoff
Plots of switchign time of nanomagnets by spin torque calculated by macrospin model and micromagnetic tool OOMMF, compared sidebyside.
D. E. Nikonov, G. I. Bourianoff, G. Rowlands, I. N. Krivorotov
Should be read and cited in conjunction with
http://arxiv.org/abs/1001.4578

Taxonomy of spintronics (a zoo of devices)
02 Nov 2006  Online Presentations  Contributor(s): Dmitri Nikonov, George Bourianoff
The presentation deals with classification of logic devices based on electron spin as a computational variable. Requirements for logic devices are reviewed. Specifically we focus on a) concatenability (output of one device can drive another) and b) the complete set of Boolean operators (NOT, AND, OR, or equivalent). Based on their inputs and outputs and schemes of interconnection, spintronic devices are classified into four groups. Proposed and demonstrated devices belonging to each group are …

Scattering in NEGF: Made simple
09 Nov 2009  Papers  Contributor(s): Dmitri Nikonov, Himadri Pal, George Bourianoff
Formalism for describing electronphonon scattering, surface scattering, and spin relaxation is dervied for the Keldysh nonequilibrium Green's functions (NEGF) method. Approximation useful for efficient numerical solution are described. The specific case of the nanoMOS simulator is considered.
Dmitri Nikonov, George Bourianoff, Paolo Gargini
Intel Corp., Components Research
Santa Clara, California, 95052
dmitri.e.nikonov@intel.com
Himadri Pal
Purdue University

Notes on Scattering and Mobility in 1D, 2D, and 3D
06 Nov 2009  Teaching Materials  Contributor(s): Dmitri Nikonov, Md. Sayed Hasan, George Bourianoff
Derivation of the phononlimited mobility is reviewed for electrons in bulk (3D) or
quantum confined (2D and 1D) semiconductor structures. Analytical estimates are made
that show the mobility in quantum confined structures is, in general, lower or no higher
than in nonconfined ones.

Animations of magnetic QCA operation
21 Oct 2007  Downloads  Contributor(s): Dmitri Nikonov, George Bourianoff
Animations of an inverter and a majority gate operation for QCA logic for the paper
"Simulation of highly idealized, atomic scale MQCA logic circuits"
by Dmitri E. Nikonov, George I. Bourianoff, Paolo A. Gargini
More detailed description to follow.

Simulation of highly idealized, atomic scale MQCA logic circuits
15 Nov 2007  Papers  Contributor(s): Dmitri Nikonov, George Bourianoff
Spintronics logic devices based on majority gates formed by atomiclevel arrangements of spins in the crystal lattice is considered. The dynamics of switching is modeled by timedependent solution of the densitymatrix equation with relaxation. The devices are shown to satisfy requirements for logic. Switching speed and dissipated energy are calculated and compared with electronic transistors. The simulations show that for the highly idealized case assumed here, it is possible to trade off size …

MOSCNT: code for carbon nanotube transistor simulation
14 Nov 2006  Downloads  Contributor(s): Siyu Koswatta, Jing Guo, Dmitri Nikonov
Ballistic transport in carbon nanotube metaloxidesemiconductor fieldeffect transistors (CNTMOSFETs) is simulated using the Nonequilibrium Green’s function formalism. A cylindrical transistor geometry with wrappedaround gate and doped source/drain regions are assumed. It should be noted that this code does NOT treat Schottkybarrier CNTFETs.

recursive algorithm for NEGF in Matlab
13 Nov 2006  Downloads  Contributor(s): Dmitri Nikonov, Siyu Koswatta
This ziparchive contains two Matlab functions for the recursive solution of the partial matrix inversion and partial 3matrix multiplication used in the nonequilibrium Green’s function (NEGF) method.
recuresealg3d.m
 works for 3diagonal matrices
recuresealgblock3d.m
 works for 3blockdiagonal matrices
The explanations of the arguments and the calling sequence are in file headers. To display, use the Matlab commands
>> help recuresealg3d
>> help recuresealgblock3d
Coauthored by Siyu ...

Modeling of Nanoscale Devices
19 Oct 2006  Papers  Contributor(s): M. P. Anantram, Mark Lundstrom, Dmitri Nikonov
We aim to provide engineers with an introduction
to the nonequilibriumGreen’s function (NEGF) approach, which is a powerful conceptual tool and a practical analysismethod to treat nanoscale electronic devices with quantum mechanical
and atomistic effects. We first review the basis for the traditional, semiclassical description of carriers that has served device engineers for more than 50 years. We then describe why this traditional approach loses validity at the nanoscale. Next, we describe ...

MATLAB DOs and DON'Ts
14 May 2006  Online Presentations  Contributor(s): Dmitri Nikonov
Matlab is widely used for simulations but is believed to be unsuitable for complex projects and to produce slowrunning software tools. The presentation argues that blind copying of methods typical of C and Fortran is responsible for such inefficiencies; the presentation teaches avoidance of these mistakes and improvement of the run time and usability of codes by using unique Matlab methods. Tools for optimizing the code and good software practices are also discussed.