Fully Printed Carbon Nanotube Transistor Circuits for Displays

Since the invention of liquid crystal displays in the mid-1960s, display electronics have undergone rapid transformation. Recently developed organic light-emitting diodes (OLEDs) have shown several advantages over LCDs, including their light weight, flexibility, wide viewing angles, improved brightness, high power efficiency and quick response. OLED-based displays are now used in cell phones, digital cameras and [...]

MadHatCreations Gone Mobile.

We are happy to inform everyone that MadHatCreations can now be accessed via mobile without having to trouble you with slow downloading embedded media. The new mobile theme is light on the bandwidth usage and quick to load so that you can have what you need when you need it on the go. You dont [...]

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Robotic bug gets wings, sheds light on evolution of flight

A six-legged, 25 gram robot has been fitted with flapping wings in order to gain an insight into the evolution of early birds and insects. Then engineers at the University of California, Berkeley, outfitted a six-legged robotic bug with wings in an effort to improve its mobility, they unexpectedly shed some light on the evolution [...]

roboticbugge roboticbugge

Could a Computer One Day Rewire Itself? New Nanomaterial ‘Steers’ Electric Currents in Multiple Dimensions

As electronic devices are built smaller and smaller, the materials from which the circuits are constructed begin to lose their properties and begin to be controlled by quantum mechanical phenomena. Reaching this physical barrier, many scientists have begun building circuits into multiple dimensions, such as stacking components on top of one another. The Northwestern team [...]

Regenerative Computers Regenerative Computers

New Method of Growing High-Quality Graphene Promising for Next-Gen Technology

Kaustav Banerjee, a professor with the Electrical and Computer Engineering department and Director of the Nanoelectronics Research Lab at UCSB that has been studying carbon nanomaterials for more than seven years, led the research team to perfect methods of growing sheets of graphene, as detailed in a study to be published in the November 2011 [...]

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Fully Printed Carbon Nanotube Transistor Circuits for Displays

December 1st, 2011 MadHatCreations No Comments »

Since the invention of liquid crystal displays in the mid-1960s, display electronics have undergone rapid transformation. Recently developed organic light-emitting diodes (OLEDs) have shown several advantages over LCDs, including their light weight, flexibility, wide viewing angles, improved brightness, high power efficiency and quick response.

OLED-based displays are now used in cell phones, digital cameras and other portable devices. But developing a lower-cost method for mass-producing such displays has been complicated by the difficulties of incorporating thin-film transistors that use amorphous silicon and polysilicon into the production process.

Now, researchers from Aneeve Nanotechnologies, a startup company at UCLA’s on-campus technology incubator at the California NanoSystems Institute (CNSI), have used low-cost ink-jet printing to fabricate the first circuits composed of fully printed back-gated and top-gated carbon nanotube-based electronics for use with OLED displays.

The startup includes collaborators from the departments of materials science and electrical engineering at the UCLA Henry Samueli School of Engineering and Applied Science and the department of electrical engineering at the University of Southern California.

In this innovative study, the team made carbon nanotube thin-film transistors with high mobility and a high on-off ratio, completely based on ink-jet printing. They demonstrated the first fully printed single-pixel OLED control circuits, and their fully printed thin-film circuits showed significant performance advantages over traditional organic-based printed electronics.

“This is the first practical demonstration of carbon nanotube-based printed circuits for display backplane applications,” said Kos Galatsis, an associate adjunct professor of materials science at UCLA Engineering and a co-founder of Aneeve. “We have demonstrated carbon nanotubes’ viable candidacy as a competing technology alongside amorphous silicon and metal-oxide semiconductor solution as a low-cost and scalable backplane option.”

This distinct process utilizes an ink-jet printing method that eliminates the need for expensive vacuum equipment and lends itself to scalable manufacturing and roll-to-roll printing. The team solved many material integration problems, developed new cleaning processes and created new methods for negotiating nano-based ink solutions.

For active-matrix OLED applications, the printed carbon nanotube transistors will be fully integrated with OLED arrays, the researchers said. The encapsulation technology developed for OLEDs will also keep the carbon nanotube transistors well protected, as the organics in OLEDs are very sensitive to oxygen and moisture.

The technology incubator at the CNSI was established two years ago to nurture early-stage research and to help speed the commercial translation of technologies developed at UCLA. Aneeve Nanotechnologies LLC has been conducting proof-of-concept work at the tech incubator with the mission of developing superior, low-cost, high-performance electronics using nanotechnology solutions that bridge the gap between emerging and traditional platforms.

The research was published this month in the journal Nano Letters.

Source: ScienceDaily

MadHatCreations Gone Mobile.

November 25th, 2011 MadHatCreations No Comments »
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We are happy to inform everyone that MadHatCreations can now be accessed via mobile without having to trouble you with slow downloading embedded media. The new mobile theme is light on the bandwidth usage and quick to load so that you can have what you need when you need it on the go. You dont have to do anything, just visit www.madhatcreations..com from your cellphone browser and we will adjust the site to your needs. Just a small thing in our attempt to help our customers.

Thank You.
Admin.

The 555 Timer.

November 25th, 2011 MadHatCreations No Comments »
aa-555-med

Most mechanical machinery work in three dimensions that is length, width and height. They also occasionally work in the forth dimension time. For example your car engine has a belt that is aligned to a particular position so that all the systems are correctly in sync with each other. But in the electronic world every thing works on time that means length, width & height are not a parameter in an electronic system. Only time, frequency, voltage and current are parameters in a electronic system. Signals are generally time variant and to keep various systems in sync with each other so that information isn’t missed out or over written or not read, we have a special circuit that is only responsible for generating a continuous pulse train. The specialty of this circuit is that it is supposed to produce pulses of exactly the same time period for a long time with almost ZERO phase shift. There are various IC that perform this task but none do it better and with greater ease then the 555 Timer IC. The 555 Timer IC is absolutely loved by hobbits and amateur engineers because of it’s simplicity of design and use. The 555 Requires at the most three external components( two resistors and a capacitor) to start doing it’s magic. The pin Diagram of the 555 is given down along with it’s description.

Pin Description

  1. GND: Self Explanatory. The ground is connected to the ground rail of the Circuit.
  2. TRIG: Trigger, this pin triggers a change in the output of the 555 Timer module. When this pin is pulled low the output goes high and the capacitor begins to charge. When the capacitor voltage reaches 2/3 Vcc Voltage the output goes low irrespective of the state of the TRIG pin. The Trigger then has to be released( connected to VCC or Left unconnected) so that the capacitor can begin discharging again. The Trigger is level triggered and must be pulled to a voltage that is less than 1/3 Vcc to be activated.
  3. OUT: Output of the 555.
  4. RESET: This is a pull-down reset pin. When this pin is pulled to ground the capacitor is completely discharged and voltage on output is cleared.
  5. CTRL:The control pin provides access to the internal control of the 555 timer IC. This pin can be used to Pulse Width modulate the ouput of the 555 with respect to a analog voltage signal.
  6. THR: This pin is the Threshold pin. This pin is a level activated pin and is directly connected to the capacitor and contineously measures the capacitor voltage level. if the level exceeds 2/3 VCC voltage the Threshold pin is activated and the Discharge pin discharges the capacitor.
  7. DIS: This pin is used to discharge the capacitor and is activated by the Threshold pin.
  8. VCC: This is the +ve power supply to the 555 and is connected to the +ve Power Rail.

Now that we have the pin diagram out of the way lets take a look at a basic 555 oscillator.

Astable: The 555 oscillator is called Astable Multivibrator. The mode is called ‘Astable’ Mode. The reason it is called ‘Astable’ is because it is not stable(Hence A-Stable) at any level. That is it continuously oscillates between +ve Vcc and Ground. This kind of circuit is mainly used to provide continuous pulses of a constant time period.

 

 

 

 

 

 

 

 

 

 

Click to see the animation.

Click Here to another animation.

Frequency is given by:

T = 0.7 × (R1 + 2R2) × C1   and  f =            1.4          
(R1 + 2R2) × C1

T   = time period in seconds (s)
f    = frequency in hertz (Hz)
R1 = resistance in ohms (ohm)
R2 = resistance in ohms (ohm)
C1 = capacitance in farads (F)

Choosing R1, R2 and C1 (Source: http://www.kpsec.freeuk.com/555timer.htm)

555 astable frequencies
C1 R2 = 10kohm
R1 = 1kohm		 R2 = 100kohm
R1 = 10kohm		 R2 = 1Mohm
R1 = 100kohm
0.001µF 68kHz 6.8kHz 680Hz
0.01µF 6.8kHz 680Hz 68Hz
0.1µF 680Hz 68Hz 6.8Hz
1µF 68Hz 6.8Hz 0.68Hz
10µF 6.8Hz 0.68Hz
(41 per min.)		 0.068Hz
(4 per min.)

R1 and R2 should be in the range 1kohm to 1Mohm. It is best to choose C1 first because capacitors are available in just a few values.

  • Choose C1 to suit the frequency range you require (use the table as a guide).
  • Choose R2 to give the frequency (f) you require. Assume that R1 is much smaller than R2 (so that Tm and Ts are almost equal), then you can use:
    R2 =    0.7  
    f × C1
  • Choose R1 to be about a tenth of R2 (1kohm min.) unless you want the mark time Tm to be significantly longer than the space time Ts.
  • If you wish to use a variable resistor it is best to make it R2.
  • If R1 is variable it must have a fixed resistor of at least 1kohm in series
    (this is not required for R2 if it is variable).

There are two other types of multivibrators, Mono-Stable and Bi-Stable. Lets take a look at what those two types are to get a better understanding of the other ways we can use the 555.

Monostable: A monostable multivibrator is not a oscillator but a signal corrector. The monostable mode of the 555 is stable only at one state that is either at +ve Vcc or ground. It is stable at one state means it can stay in that state for as long as there is no external trigger. If there is a external trigger the 555′s output will change for a small amount of time and then the output will return to the stable state. The monostable mode is used mainly in systems where the input must be provided only for some amount of time or else the system will give an error. It is also used as a switch debouncer. An example of the monostable mode of the 555 is shown below.

Click To enlarge.

Click Here to see animation.

Frequency of Monostable is given by:

The duration of the pulse is called the time period (T) and this is determined by resistor R1 and capacitor C1:

time period, T = 1.1 × R1 × C1

T   = time period in seconds (s)
R1 = resistance in ohms (ohm)
C1 = capacitance in farads (F)
The maximum reliable time period is about 10 minutes.

  • Choose C1 first (there are relatively few values available).
  • Choose R1 to give the time period you need. R1 should be in the range 1kohm to 1Mohm, so use a fixed resistor of at least 1kohm in series if R1 is variable.
  • Beware that electrolytic capacitor values are not accurate, errors of at least 20% are common.
  • Beware that electrolytic capacitors leak charge which substantially increases the time period if you are using a high value resistor – use the formula as only a very rough guide!

 

Bi-Stable: The Last mode in the 555 is the Bi-Stable. In the bi-stable mode, the 555, doesn’t oscillate at all. The 555 is stable in both stages. Example of Bi-Stable circuits is the Flip Flop. When the flip Flop is set it’s output remains constant until reset signal is applied. That means the Flip Flop is stable in both high and low stages. The 555 Can be used as a flip flop also. The circuit below shows how a 555 can be used as a flip flop.

 

 

 

 

 

 

 

 

 

 

Click image to enlarge.

Click Here to view Animation.

Hope this post has quenched your thirst for knowledge on the 555 Timer. Best of luck!

Atmega32 Digital Thermometer with PWM Fan Control and LCD Display

November 4th, 2011 MadHatCreations 1 Comment »
Digital Thermometer with PWM

Right, Now down to the fun part. We are to assume that you have read all the previous posts about the basics of all the mentioned components accept the Digital Thermometer-part. This will be our first full project. This project consists of three parts one is the LCD module Interface, the second involves the use of the timer module and the third involves the use of the ADC module of the ATMEGA32.

If you need quick refference to all these components keep these links open:

  1. Timer Module
  2. LCD Module
  3. Analog to digital Converter Module

For the digital thermometer we are going to use an IC called the LM35, It doesn’t really look like an IC but it is one mighty powerful thing. On the outside it looks like a typical NPN transistor but mind you it isn’t. The LM35 has a simple analog output for every degree rise in temprature the output increases by 10mV. That means the output is 10mV/°C. Now we know that our analog to digital converter has 10bit output, so 210=1024. But we know that our Vref=5V that means the digital output will be with refference to 5V and that maximum possiable output of the ADC is 0b1111111111 is at analog signal=5V. So the ADC will change it’s value at every 5/1024=5mV rise in input voltage.

But the LM35′s output increases by 10mV/°C and the ADC increases by 5mV. That means for every one degree rise in temprature, the ADC value will rise by 2. Hence half the value of the ADC’s value will be our temprature.

So now that we cleared the basics of how this circuit will work lets take a look at the circuit diagram.

Now, let us take a look at the differnet functions we will define and their purpose:

  1. initLCD() : We will call this function to initilize our LCD module.
  2. initPWM() : This function will start and configure our Timer0 module.
  3. initADC() : This function will configure the Analog to Digital Converter for us.
  4. LCD_data(unsigned char data) : Writes data to LCD module.
  5. LCD_comm(unsigned char data) : Sends Command to LCD module.
  6. readADC(): Reads the data from the ADC module.
  7. setOCR: Sets the duty cycle of the PWM timer0 module.
  8. LCDnum(double number) : This is a real cool function it converts the decimal value of the ADC value division into char format for the LCD to display. More on how that works later.

LCD PORTS are PORTC for data and PORTD(6 & 7 bits) for ‘E’ and ‘RS’ respectively.

 

Everything Set? Ok, down to the actual program.

/*First program the CPU speed for the delay routines */

#delay F_CPU 4000000UL

/*Include the necessary files.*/

#include <avr/io.h>

#include <util/delay.h>

#define setBitE PORTD|=_BV(PD7);                /*Used to set pin PD7 which is connected to Enable ‘E’ of LCD module.*/
#define clearBitE PORTD&=~(_BV(PD7));                /*Used to clear pin PD7 which is connected to Enable ‘E’ of LCD module.*/

#define setBitRS PORTD|=_BV(6);                /*Used to set pin PD6 which is connected to Registry Select ‘RS’ of LCD module.*/
#define clearBitRS PORTD&=~(_BV(6));                /*Used to clear pin PD6 which is connected to Registry Select ‘RS’ of LCD module.*/

#define newLine LCD_comm((0×80+0×40));                /*Used to Go to the next line whose starting charecter address in 0×40*/

/*Prottype the functions*/

void initLCD();

void initADC();

void initPWM();

void LCD_data(unsigned char data);

void LCD_comm(unsigned char data);

void LCDnum(double number);

double readADC();

void setOCR(unsigned char value);

void printLine(unsigned char data[], int num);

/*Declare the functions*/

void LCD_data(unsigned char data)
{
clearBitE;
setBitRS;
PORTC=data;
setBitE;
_delay_ms(3);
clearBitE;
_delay_ms(3);
clearBitRS;
_delay_ms(2);
PORTC=0;
}

void LCD_comm(unsigned char comm)
{
clearBitE;
clearBitRS;
PORTC=comm;
setBitE;
_delay_ms(3);
clearBitE;
_delay_ms(3);
PORTC=0;
}

void initLCD()
{
DDRD=0b11111111;
PORTD=0;
DDRC=0b11111111;
PORTC=0;
_delay_ms(10);
LCD_comm(48);
_delay_ms(20);
LCD_comm(48);
_delay_ms(20);
LCD_comm(48);
_delay_ms(20);
LCD_comm(56);
_delay_ms(20);
LCD_comm(6);
_delay_ms(20);
LCD_comm(12);
_delay_ms(20);
LCD_comm(1);
_delay_ms(20);
}

void printLine(unsigned char data[], int num)
{
int i=0;
while(i<num)
{
LCD_data(data[i]);
i=i+1;
}
}

void initADC()
{
DDRA=0b00000000;
PORTA=0b00000000;
ADMUX|=(1<<REFS0);
ADCSRA|=(1<<ADEN)|(1<<ADPS2)|(1<<ADPS0);
}

double readADC()
{
ADCSRA|=(1<<ADSC);
while((ADCSRA&(1<<ADIF))==0);
return ADC;
}

void LCDnum(double number)
{
unsigned char digit;

digit=’0′;
while(number>=1000)
{
digit++;
number=number-1000;
}
if(digit!=’0′)
LCD_data(digit);

digit=’0′;
while(number>=100)
{
digit++;
number=number-100;
}
if(digit!=’0′)
LCD_data(digit);

digit=’0′;
while(number>=10)
{
digit++;
number=number-10;
}
if(digit!=’0′)
LCD_data(digit);

digit=’0′;
while(number>=1)
{
digit++;
number=number-1;
}
LCD_data(digit);

digit=’0′;
while(number>=0.1)
{
digit++;
number-=0.1;
}
LCD_data(‘.’);
LCD_data(digit);

digit=’0′;
while(number>=0.01)
{
digit++;
number-=0.01;
}
LCD_data(digit);
}

void setupPWM()
{
TCCR0|=(1<<CS01)|(1<<CS00)|(1<<COM01)|(0<<COM00)|(1<<WGM00)|(1<<WGM01);
OCR0=115;
}
void setOCR(double ocr_value)
{
OCR0=ocr_value;
}

int main()
{
DDRB=255;
PORTB=255;
_delay_ms(200);
initLCD();
initADC();

initPWM();

printLine(“Goodday!”, 8);
_delay_ms(2000);
LCD_comm(1);
printLine(“I am a digital”, 14);
newLine;
printLine(“Thermometer.”, 12);
_delay_ms(2000);
LCD_comm(1);
double a[4];
while(1)
{

/*Find mean of ADC values to give less error.*/
a[0]=readADC();
_delay_ms(10);
a[1]=readADC();
_delay_ms(10);
a[2]=readADC();
_delay_ms(10);
a[4]=((a[0]+a[1]+a[2])/6);

printLine(“Temp:”, 5);

LCDnum(b[0]);
LCD_data(0b11011111);
LCD_data(‘C’);
newLine;

printLine(“Duty Cycle”);
LCDnum((a[4]*2));

setOCR((a[4]*2));
_delay_ms(1500);
LCD_comm(1);
}
return 0;
}

Robotic bug gets wings, sheds light on evolution of flight

October 18th, 2011 MadHatCreations No Comments »
roboticbugge

A six-legged, 25 gram robot has been fitted with flapping wings in order to gain an insight into the evolution of early birds and insects. Then engineers at the University of California, Berkeley, outfitted a six-legged robotic bug with wings in an effort to improve its mobility, they unexpectedly shed some light on the evolution of flight.

Even though the wings significantly improved the running performance of the 10-centimeter-long robot – called DASH, short for Dynamic Autonomous Sprawled Hexapod – they found that the extra boost would not have generated enough speed to launch the critter from the ground. The wing flapping also enhanced the aerial performance of the robot, consistent with the hypothesis that flight originated in gliding tree-dwellers.

The research team, led by Ron Fearing, professor of electrical engineering and head of the Biomimetic Millisystems Lab at UC Berkeley, reports its conclusions online Tuesday, Oct. 18, in the peer-reviewed journal Bioinspiration and Biomimetics. Using robot models could play a useful role in studying the origins of flight, particularly since fossil evidence is so limited, the researchers noted. First unveiled by Fearing and graduate student Paul Birkmeyer in 2009, DASH is a lightweight, speedy robot made of inexpensive, off-the-shelf materials, including compliant fiber board with legs driven by a battery-powered motor. Its small size makes it a candidate for deployment in areas too cramped or dangerous for humans to enter, such as collapsed buildings.

A robot gets its wings

But compared with its biological inspiration, the cockroach, DASH had certain limitations as to where it could scamper. Remaining stable while going over obstacles is fairly tricky for small robots, so the researchers affixed DASH with lateral and tail wings borrowed from a store-bought toy to see if that would help. “Our overall goal is to give our robots the same all-terrain capabilities that other animals have,” said Fearing. “In the real world, there will be situations where flying is a better option than crawling, and other places where flying won’t work, such as in confined or crowded spaces. We needed a hybrid running-and-flying robot.”

The researchers ran tests on four different configurations of the robotic roach, now called DASH+Wings. The test robots included one with a tail only and another that just had the wing’s frames, to determine how the wings impacted locomotion. With its motorized flapping wings, DASH+Wings’ running speed nearly doubled, going from from 0.68 meters per second with legs alone to 1.29 meters per second. The robot could also take on steeper hills, going from an incline angle of 5.6 degrees to 16.9 degrees.

“With wings, we saw improvements in performance almost immediately,” said study lead author Kevin Peterson, a Ph.D. student in Fearing’s lab. “Not only did the wings make the robot faster and better at steeper inclines, it could now keep itself upright when descending. The wingless version of DASH could survive falls from eight stories tall, but it would sometimes land upside down, and where it landed was partly guided by luck.”

The flapping wings improved the lift-drag ratio, helping DASH+Wings land on its feet instead of just plummeting uncontrolled. Once it hit the ground, the robot was able to continue on its way. Wind tunnel experiments showed that it is aerodynamically capable of gliding at an angle up to 24.7 degrees.

Tree-dwellers vs. ground-runners

The engineering team’s work caught the attention of animal flight expert Robert Dudley, a UC Berkeley professor of integrative biology, who noted that the most dominant theories on flight evolution have been primarily derived from scant fossil records and theoretical modeling. He referenced previous computer models suggesting that ground-dwellers, given the right conditions, would need only to triple their running speed in order to build up enough thrust for takeoff. The fact that DASH+Wings could maximally muster a doubling of its running speed suggests that wings do not provide enough of a boost to launch an animal from the ground. This finding is consistent with the theory that flight arose from animals that glided downwards from some height.

“The fossil evidence we do have suggests that the precursors to early birds had long feathers on all four limbs, and a long tail similarly endowed with a lot of feathers, which would mechanically be more beneficial for tree-dwelling gliders than for runners on the ground,” said Dudley. Dudley said that the winged version of DASH is not a perfect model for proto-birds – it has six legs instead of two, and its wings use a sheet of plastic rather than feathers – and thus cannot provide a slam-dunk answer to the question of how flight evolved.

“What the experiments did do was to demonstrate the feasibility of using robot models to test hypotheses of flight origins,” he said. “It’s the proof of concept that we can actually learn something useful about biological performance through systematic testing of a physical model.”

Among other robotic insects being tested in the Biomimetic Millisystems Lab is a winged, bipedal robot called BOLT (Bipedal Ornithopter for Locomotion Transitioning) that more closely resembles the size and aerodynamics of precursors to flying birds and insects.

“It’s still notable that adding wings to DASH resulted in marked improvements in its ability to get around,” said Fearing. “It shows that flapping wings may provide some advantages evolutionarily, even if it doesn’t enable flight.”

Source: PhysOrg

Could a Computer One Day Rewire Itself? New Nanomaterial ‘Steers’ Electric Currents in Multiple Dimensions

October 18th, 2011 MadHatCreations No Comments »
Regenerative Computers

As electronic devices are built smaller and smaller, the materials from which the circuits are constructed begin to lose their properties and begin to be controlled by quantum mechanical phenomena. Reaching this physical barrier, many scientists have begun building circuits into multiple dimensions, such as stacking components on top of one another.

The Northwestern team has taken a fundamentally different approach. They have made reconfigurable electronic materials: materials that can rearrange themselves to meet different computational needs at different times. “Our new steering technology allows use to direct current flow through a piece of continuous material,” said Bartosz A. Grzybowski, who led the research. “Like redirecting a river, streams of electrons can be steered in multiple directions through a block of the material — even multiple streams flowing in opposing directions at the same time.” Grzybowski is professor of chemical and biological engineering in the McCormick School of Engineering and Applied Science and professor of chemistry in the Weinberg College of Arts and Sciences.

The Northwestern material combines different aspects of silicon- and polymer-based electronics to create a new classification of electronic materials: nanoparticle-based electronics. The study, in which the authors report making preliminary electronic components with the hybrid material, will be published online Oct. 16 by the journal Nature Nanotechnology. The research also will be published as the cover story in the November print issue of the journal.

“Besides acting as three-dimensional bridges between existing technologies, the reversible nature of this new material could allow a computer to redirect and adapt its own circuitry to what is required at a specific moment in time,” said David A. Walker, an author of the study and a graduate student in Grzybowski’s research group.

Imagine a single device that reconfigures itself into a resistor, a rectifier, a diode and a transistor based on signals from a computer. The multi-dimensional circuitry could be reconfigured into new electronic circuits using a varied input sequence of electrical pulses. The hybrid material is composed of electrically conductive particles, each five nanometers in width, coated with a special positively charged chemical. (A nanometer is a billionth of a meter.) The particles are surrounded by a sea of negatively charged atoms that balance out the positive charges fixed on the particles. By applying an electrical charge across the material, the small negative atoms can be moved and reconfigured, but the relatively larger positive particles are not able to move.

By moving this sea of negative atoms around the material, regions of low and high conductance can be modulated; the result is the creation of a directed path that allows electrons to flow through the material. Old paths can be erased and new paths created by pushing and pulling the sea of negative atoms. More complex electrical components, such as diodes and transistors, can be made when multiple types of nanoparticles are used.

The title of the paper is “Dynamic Internal Gradients Control and Direct Electric Currents Within Nanostructured Materials.” In addition to Grzybowski and Walker, other authors are Hideyuki Nakanishi, Paul J. Wesson, Yong Yan, Siowling Soh and Sumanth Swaminathan, from Northwestern, and Kyle J. M. Bishop, a former member of the Grzybowski research group, now with Pennsylvania State University.

Source: ScienceDaily

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