According to Gaidarzhy, during the past several decades engineers have made phenomenal advances in information technology by shrinking electronic circuitry and devices to fit onto semiconductor chips. Shrinking electronic or mechanical systems further, he says, will inevitably require new paradigms involving quantum theory. For example, these mechanical/quantum mechanical hybrids could be used for quantum computing.
Because Mohanty’s nanomechanical oscillator is “large,” the research team was able to attach electrical wiring to its surface in order to monitor tiny discrete quantum motion, behavior that exists in the realm of atoms and molecules.
At a certain frequency, the paddles begin to vibrate in concert, causing the central beam to move at that same high frequency, but at an increased and easily measured amplitude. Where each paddle moves only about a femtometer, roughly the diameter of an atom’s nucleus, the antenna moves over a distance of one-tenth of a picometer, a tiny distance that still translates to a 100-fold increase in amplitude.
When fabricating and testing the nanomechanical device, the researchers placed the entire apparatus, including the cryostat and monitoring devices, in a state-of-the-art, copper-walled, copper-floored room. This set-up shielded the experiment from unwanted vibration noise and electromagnetic radiation that could generate from outside electrical devices, such as cell phone signals, or even the movement of subway trains outside the building.
Even with these precautions, performing such novel experiments is tricky. “When it’s a new phenomenon, it’s best not to be guided by expectations based on conventional wisdom,” says Gaidarzhy. “The philosophy here is to let the data speak for itself.”
In addition to Gaidarzhy, Mohanty’s team consists of Guiti Zolfagharkhani, a graduate student, and Robert L. Badzey, a post-doctoral fellow in BU’s Physics Department. Their paper appears in the January 28, 2005 issue of Physical Review Letters. The research was supported by grants from the National Science Foundation, Department of Defense, Petroleum Research Fund, and the Sloan Foundation.
Text for this article comes from a BU press release.