EPSRC Reference: |
EP/C540182/1 |
Title: |
Dissipative Dynamics of Nanoelectromechanical Systems |
Principal Investigator: |
Armour, Professor A |
Other Investigators: |
|
Researcher Co-Investigators: |
|
Project Partners: |
|
Department: |
Sch of Physics & Astronomy |
Organisation: |
University of Nottingham |
Scheme: |
Advanced Fellowship (Pre-FEC) |
Starts: |
01 October 2005 |
Ends: |
30 September 2010 |
Value (£): |
233,436
|
EPSRC Research Topic Classifications: |
Condensed Matter Physics |
Materials Characterisation |
|
EPSRC Industrial Sector Classifications: |
|
Related Grants: |
|
Panel History: |
Panel Date | Panel Name | Outcome |
18 Apr 2005
|
Physics Fellowship Interview Panel
|
Deferred
|
07 Mar 2005
|
Physics Fellowships Sifting Panel 2005
|
Deferred
|
|
Summary on Grant Application Form |
When you twang a guitar string it vibrates and as it does so it forces the air around it into motion, giving rise to the sound you hear. Of course the string eventually stops moving because as it sets the air in motion about it, it loses energy and so slows down. This project is about the behaviour of tiny strings, called nanomechanical resonators, which are about a million times smaller than a guitar string. The frequency, or pitch, of a note that comes from a string depends on how long the string is. For a guitar the frequency is just right for humans to hear it, but for nanomechanical resonators the frequency is much higher, about the same as for radio waves, and so is well beyond our hearing. However, it is possible to 'listen' to the vibrations of a nanomechanical resonator using electrical circuitry and detect very subtle changes in the frequency of the notes.Although nanomechanical resonators are no good as musical instruments, they can be useful for a lot of other things. For example, nanomechanical resonators can be used as a fantastically sensitive set of scales. Because a nanomechanical resonator itself weighs very little, placing a small object, like a biological virus, on top of the resonator changes the frequency of the vibrations in a way that depends on how much the object weighs. But there is a catch: In order to weigh things accurately we need to be able to measure very small changes in the frequency of the nanomechanical resonator, and to be able to do that the resonator must vibrate long enough at the same frequency for an accurate measurement to be made. Just like guitar strings, nanomechanical resonators don't vibrate forever. Even though all the air can be removed from around nanomechanical resonators, they still lose energy to their surroundings or even to the electrical circuitry which is used to measure them. What is worse, the smaller a nanomechanical resonator is made, the faster its vibrations tend to decay away. One of the key aims of this project is to try and understand why the vibrations of a nanomechanical resonators damp away so fast. Once we understand exactly why nanomechanical resonators lose energy so fast to their surroundings, and how they are affected by the electrical circuitry used to measure them, it should be possible to improve their design to ensure that they vibrate for longer and so can be used to weigh even smaller objects, like individual molecules.This project will also address some issues which are very fundamental in physics. Microscopic objects, like atoms or molecules, are known to behave in a very different way to everyday objects like footballs. For example, there is a very important rule, known as the Uncertainty Principle which states that it is impossible to know everything about the motion of an object at any one instant. Although physicists know that microscopic objects, like atoms, obey the Uncertainty Principle, everyday objects seem to follow different laws that allow us to know both where they are and how fast they are going at the same time. Nanomechanical resonators are very small on the scale of everyday objects, but large on the scale of atoms (they each contain many billions of atoms) so they lie somewhere between the microscopic and the macroscopic worlds. Part of this project will involve working out how nanomechanical resonators, because of there position somewhere in-between, can be used to investigate exactly how the differences in behaviour between macroscopic and microscopic objects arise.
|
Key Findings |
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
|
Potential use in non-academic contexts |
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
|
Impacts |
Description |
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk |
Summary |
|
Date Materialised |
|
|
Sectors submitted by the Researcher |
This information can now be found on Gateway to Research (GtR) http://gtr.rcuk.ac.uk
|
Project URL: |
|
Further Information: |
|
Organisation Website: |
http://www.nottingham.ac.uk |