Good vibrations: New atom-scale products on horizon

Aug 23, 2010
This is a laser in Dr. Kambhampati's lab that is used to shine light on quantum dots. Credit: Credit: Dept. of Chemistry, McGill University.

The generation of an electric field by the compression and expansion of solid materials is known as the piezoelectric effect, and it has a wide range of applications ranging from everyday items such as watches, motion sensors and precise positioning systems. Researchers at McGill University's Department of Chemistry have now discovered how to control this effect in nanoscale semiconductors called "quantum dots," enabling the development of incredibly tiny new products.

Although the word "quantum" is used in everyday language to connote something very large, it actually means the smallest amount by which certain physical quantities can change. A quantum dot has a diameter of only 10 to 50 atoms, or less than 10 nanometres. By comparison, the diameter of the DNA double-helix is 2 nanometres. The McGill researchers have discovered a way to make individual charges reside on the surface of the dot, which produces a large electric field within the dot. This electric field produces enormous piezoelectric forces causing large and rapid expansion and contraction of the dots within a trillionth of a second. Most importantly, the team is able to control the size of this vibration.

can be used in a wide range of technological applications. Solar power is one area that has been explored, but this new discovery has paved way for other nanoscale device applications for these dots. This discovery offers a way of controlling the speed and switching time of , and possibly even developing nanoscale power supplies, whereby a small compression would produce a large voltage.

"The has never been manipulated at this scale before, so the range of possible applications is very exciting," explained Pooja Tyagi, a PhD researcher in Professor Patanjali Kambhampati's laboratory. "For example, the vibrations of a material can be analyzed to calculate the pressure of the solvent they are in. With further development and research, maybe we could measure blood pressure non-invasively by injecting the dots, shining a laser on them, and analyzing their vibration to determine the pressure." Tyagi notes that Cadium Selenide is a toxic metal, and so one of the hurdles to overcome with regard to this particular example would be finding a replacement material.

Explore further: Scientists unveil new technology to better understand small clusters of atoms

More information: The research was published in Nano Letters.

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User comments : 8

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Nikola
5 / 5 (1) Aug 23, 2010
"Although the word "quantum" is used in everyday language to connote something very large..."

It is?
garcialovesme
5 / 5 (1) Aug 23, 2010
I think this refers to quantum leap. Can't think of any other widely used term..
danman5000
5 / 5 (3) Aug 23, 2010
With further development and research, maybe we could measure blood pressure non-invasively

I really don't know what he's thinking of, but we already have a non-invasive measurement device - it's called a sphygmomanometer.
jselin
5 / 5 (2) Aug 23, 2010
Instead of just sensing, driving these with a voltage could provide nano actuation. If you dropped the size scale another order of magitude or so more things get even more interesting... heat is atomic vibration so maybe with enough information we can manipulate that such as active cancellation, or make it coherent, or, or, or... it could potentially be a whole new frontier (or am I off in the grass?)
Skeptic_Heretic
5 / 5 (1) Aug 23, 2010
With further development and research, maybe we could measure blood pressure non-invasively

I really don't know what he's thinking of, but we already have a non-invasive measurement device - it's called a sphygmomanometer.

I presume that they mean without touching the patient.

Invasive isn't necessarily an internal process but rather the act of physical interaction in most medical circles.
danman5000
not rated yet Aug 23, 2010
With further development and research, maybe we could measure blood pressure non-invasively

I really don't know what he's thinking of, but we already have a non-invasive measurement device - it's called a sphygmomanometer.

I presume that they mean without touching the patient.

Invasive isn't necessarily an internal process but rather the act of physical interaction in most medical circles.

I was under the impression that invasive meant something internal or particularly disruptive - thanks for the clarification.
trekgeek1
not rated yet Aug 24, 2010
With further development and research, maybe we could measure blood pressure non-invasively

I really don't know what he's thinking of, but we already have a non-invasive measurement device - it's called a sphygmomanometer.

I presume that they mean without touching the patient.

Invasive isn't necessarily an internal process but rather the act of physical interaction in most medical circles.


While that makes sense and all, if you're afraid of having your bicep massaged, you probably shouldn't go to the doctor. If they stop after the Sphygmo, you're lucky since there is usually far more to come. "Uh, yeah doc, before you check my prostate, is there any less invasive way to check my blood pressure?"
DaveGee
5 / 5 (1) Aug 26, 2010
Yea but as someone with lots of inpatient experience... It would be SO nice not being woke up every 3 hours just to get my BP oxygen and body temp.

This I think is what the man is referring to as noninvasive... Nothing like being injecyed w/syringes filled with toxic medicine that makes you SO sick you often think how things might be better not getting the treatments ( forever ) and just let nature take it's course.. Then fall asleep cause you just can't stand the feeling and then being woken up 3 or more times by somebody looking to record something.

However, I for one have too much fight left in me so I keep pulling myself off the mat and going back in the ring for anotherb round...