International Journal of Modern Nonlinear Theory and Application, 2013, 2, 223-227
Published Online December 2013 (http://www.scirp.org/journal/ijmnta)
http://dx.doi.org/10.4236/ijmnta.2013.24031
Open Access IJMNTA
Dynamics and Synchronization of Memristor-Based
Fractional-Order System
Hongmin Deng
*
, Qionghua Wang
School of Electronics and Information Engineering, Sichuan University, Chengdu, China
Email:
*
hm_deng@scu.edu.cn
Received October 21, 2013; revised November 18, 2013; accepted November 24, 2013
Copyright © 2013 Hongmin Deng, Qionghua Wang. This is an open access article distributed under the Creative Commons Attribu-
tion License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly
cited.
ABSTRACT
A memristor-based fractional order circuit derived from Chua’s topology is presented. The dynamic properties of this
circuit such as phase trajectories, time evolution characteristics of state variables are analyzed through the approxima-
tion method of fractional order operator. In addition, it clearly describes the relationships between the impedance varia-
tion of the memristor and the varying mobility of the doped region of the memristor in different circuit parameters. Fi-
nally, a periodic memristor-based system driven by another chaotic memristor-based fractional order system is syn-
chronized to chaotic state via the linear error feedback technique.
Keywords: Memristor; Fractional Order; Simulation; Synchronization
1. Introduction
Since professor Chua predicted the fourth basic element
“memristor” [1], it took until 2008 for the element to be
demonstrated its existence [2]. A memristor device in
nanotechnology based on TiO
2
thin film was imple-
mented in Hewlett-Packard (HP) labs, followed by sev-
eral other materials and methods [3-5]. And this kind of
device may be expected to reform the future computers
by using it in place of random access memory (RAM).
After this landmark work [2], the increasing researches in
this topic from many perspectives such as the nonlinear
dynamics and chaotic circuit based on memristor, de-
layed switching in memristor and memristive systems,
memristive neural networks are emerged in [6-10]. How-
ever, only a few papers involving the memrisor-based
fractional order system have been reported so far, and the
research on synchronization of fractional order memris-
tive system is even less. For example, a fractional order
Chua’s circuit with a memristor and a negative conduc-
tance have been studied in [11], and the synchronization
based on memristor but limited to integer-order system
has been investigated in [12] due to its potential applica-
tions in secure communication. In this paper a new mem-
ristor-based fractional order system is investigated. Fur-
thermore, it clearly shows the detailed variation of the
memristor’s impedance as time goes. Most importantly,
the synchronization of memristor-based fractional order
systems is achieved between two systems with different
nonlinear dynamic properties originally.
The rest of the paper is organized as follows: in Sec-
tion 2, a memristor-based fractional order system model
is depicted. In Section 3, some illustrative examples and
numerical simulation results are presented. Finally, the
conclusion is drawn in Section 4.
2. Model
Memristor is a nonlinear element. It shows the v-i rela-
tionship following Ohm’s law, and the equivalent resis-
tance in HP memristor [10] is depicted by:
1
ON OFF
RH R HD R HD
.
(1)
where
denotes the internal state variable (the width
of doped area in the memristor), and
D denotes the
whole thickness of the memristor, is the equiva-
len
t resistance of the memristor with respect to the inter-
nal variable.
RH
In
Figure 1, the model is derived from the topology of
modified Chua’s circuit, where denotes the con-
duct
ance of a negative resistor, and
G
R is a positive
linear resistor.
The dynamic in the circuit of Figure 1 is expressed by
*
Corresponding author.