News & Analysis
Comment
iniewski
Very interesting research. Can one harvest any reasonable amounts of energy for ...
pixies
It is interesting to see that piezo effect still exists in the 10 nm size ...
McGill harnessing piezo effect in quantum dots for nano sensors
R. Colin Johnson
8/23/2010 2:04 PM EDT
Piezoelectric effects translate mechanical motion into electricity and vice versa, energizing a variety of electronic transducer applications as well as promising to cut power consumption in MEMS devices. Now McGill University researchers are harnessing the piezoelectric effect in quantum dots, aiming for nanoscale sensors and power supplies that translate vibration into a usable signal.
The research program, led by professor Patanjali Kambhampati, has already discovered a method for producing a large electrical field in cadmium selenide quantum dots by assembling an electronic charge around their exterior. Because of the dots' small size—only 10 to 50 atoms, or about 10 nanometers, in diameter—the internal electric field can be enormous, producing immediate expansion and contractions cycles in under a trillionth of a second, according to the researchers.
The team currently is learning to control the frequency and size of the induced vibration, with an eye toward controlling the switching time of future electronic devices based on the effect. Once control of the vibrations is achieved, the researchers plan to try reversing the effect, hoping to produce a relatively large voltage from a tiny, environmentally induced compression.
Applications could include measuring the pressure in a fluid noninvasively by adding piezoelectric quantum dots, energizing them with a laser and then measuring the piezoelectrically induced vibrations.
The research team includes doctoral candidate Pooja Tyagi. Funding agencies include the Canada Foundation for Innovation, the Natural Sciences and Engineering Research Council of Canada and Fonds Québécois de la Recherche sur la Nature et les Technologies.
|
|
|
|
|
DrQuine
8/23/2010 3:23 PM EDT
The use of quantum dots as MEMS devices which produce electricity from motion or produce motion when electricity is applied provides a new domain for innovation. Quantum dots have already been in the news for their ability to produce pure colored lights (color wavelength depending on quantum dot dimensions) and for the potential of entangled quantum dots (qubits) in quantum computing devices. As we celebrate the 50th anniversary of laser, it is interesting to speculate where innovation in quantum dots may be leading us.
Sign in to Reply
BMN
8/24/2010 10:30 AM EDT
The NWO will use nano sensors to secretly monitor every aspect of our lives.
Sign in to Reply
hm
8/24/2010 10:43 AM EDT
It will be interesting to see far reaching applications of this new concept and research. I am eager to know calibration aspect for these sensor systems. What will be typical accuracy and repeatability for these types of sensors? Can we employ them for high frequency or impulse input to sense mechanical shock?
Sign in to Reply
pixies
8/24/2010 4:52 PM EDT
It is interesting to see that piezo effect still exists in the 10 nm size regime. Usually due to the small size and large surface area the piezo effect is "relaxed" when the particle size is smaller than 10s of nanometers.
Sign in to Reply
iniewski
8/24/2010 10:06 PM EDT
Very interesting research. Can one harvest any reasonable amounts of energy for self-powered wireless nodes in this way in the future?
Sign in to Reply