Bistability electric

This paper is a report on stable and reproducible current-controlled bistable electrical switching and memory phenomena observed in polycrystalline metal-organic semiconducting films. 

Finally, we would like to mention the work of Fauve and Heslot, who studied the contemporary action of a periodic and stochastic force on a bistable electric syston. They found that applied force and noise exhibit resonant behavior. Resonance takes place when the external force time period is equal to the Kramers rate of esoq)e. ... 

Recently, a non-volatile digital memory device was fabricated using PANI nanofiber (diameter ca. 30 nm) decorated with gold nanoparticles (diameter below 5 nm) [317]. As shown in Fig. 7a, the polymer memory device displayed bistable electrical behavior (ON/OFF states). The transition from the OFF state to the ON state was ascribed to an electric field-induced charge transfer between the PANI nanofibers and the gold nanoparticles. The write-read-erase cycle tests could also be performed more than seven times (Fig. 7b). 

Nonlinear optical effects can also be used to produce bistable devices that are similar in operation to bistable electric circuits. They have potential use in optical memories and the control of optical beams and can perform... 

Figure 8.34 Left Gold focal conics of MHOBOW coexisting with accordion domains in 4-p.m SSFLC cell. Cell has not seen electric field. Right Same area after brief application of field above threshold for causing textural change of focal conics from gold SmA-like to bistable blue SmC -like. Transition from gold to bistable blue is still incomplete in this photomicrograph clear domain walls between two textures are easily seen.

Charge transfer complexes have also been investigated as the most attractive candidate materials for high-density electrical data storage.76,77 For instance, sil-ver-tetracyanoquinodimethane (Ag-TCNQ) and copper-tetracyanoquinodimethane (Cu-TCNQ) have been studied for data recording since they exhibit electrical bistability. 

Of much interest are the electroluminescence properties of conjugated polymers that allow the development of electrically switched light-emitting devices [8.257]. Electric field activated bistable molecules are expected to switch at a critical field strength [8.258]. 

In general, optically, electrically or chemically triggered switches would seem to be preferable to mechanically activated ones, as are photo-, electro- and chemo devices with respect to mechano devices and electronic or photonic computing with respect to mechanical computing. The ultimate in (nano)mechanical manipulation of a molecular device is represented by the realization of a bistable switch based on the motion of a single atom by means of the scanning tunnelling microscope [8.295] (see also Section 9.9). 

Such controlled motion might become even more important, if one realizes that a bistable, controllable rotaxane might be useful as a nanoscale electronic device. One state would then be the "0", the other would represent the 1" state of one bit of a computer memory. Even if we have a long way to go before using these molecules as reliable functional units in electrical circuits minimized to nanometer dimensions, it seems to be of great promise and such promise demands the intense study of ways to synthesize these molecules and the detailed examination of their properties. 

Landauer studied the behavior of a bistable system consisting of a tunnel diode and focused his attention on the activation jump between the two states resulting from thermal fluctuations. Later, Matsuno ° analyzed the power spectrum of the noise affecting the electric conductivity of a Gunn diode. Diode oscillations were proven to be accompanied by modulation of both amplitude and frequency. The noise spectrum was shown to exhibit typical 1// characteristics, and fluctuations were found to appear in the region close to the critical threshold with an increasing relaxation time as the threshold was approached. This behavior is largely reminiscent of that ex-... 

L.P. Ma, J. Liu and Yang, Y. (2002) Organic electrical bistable devices and rewritable memory cells Appl Phys. Lett. 80 2997. 

For a given N-shaped current-potential characteristic, there are two parameters that determine the bistable region. Re and U. In the U/Rg parameter diagram, this region becomes broader while shifting toward larger values of U for increasing, irrespective of the electrochemical reaction [Fig. 2(c)]. Below we will see that this feature is also encountered in all more complicated electrical models that describe simple or complex oscillatory behavior since all of them require an N-shaped polarization curve. 

The simplest manifestation of self-organization in a reacting system is the occurrence of bistability, that is, the coexistence of two locally stable homogeneous states. In all electrical models, bistable behavior results from the interaction of an N-shaped stationary polarization curve with a sufficiently large ohmic resistor in the external circuit. These two features also represent the backbone for all more complex forms of self-organization where, owing to exactly these two properties of the system, the double-layer potential takes on the role of the autocatalytic variable. 

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