Nanoscale Molecular Tweezers

Thermal tweezers for surface manipulation with nanoscale resolution

In this letter, we demonstrate that random Brownian forces can be used for effective trapping and manipulation of nanoparticles and molecules on surfaces in the presence of strong temperature modulation. Substantial (~ 2 orders of magnitude) increase in the modulation of particle concentration (trapping efficiency) compared to thermophoresis in a bulk medium is predicted and explained by a peri...

Line Optical Tweezers Instrument for Measuring Nanoscale Interactions and Kinetics

We describe an optical tweezers instrument for measuring short-ranged colloidal interactions, based on a combination of a continuous wave line optical tweezers, high speed video microscopy, and laser illumination. Our implementation can measure the separation of two nearly contacting microspheres to better than 4 nm at rates in excess of 10 kHz. A simple image analysis algorithm allows us to se...

DNA hybridization catalysts and molecular tweezers

We demonstrate new methods for the control of DNA hybridiza tion formation of a loop with a protective strand is used to inhibit hybridiza tion and a DNA catalyst that opens the loop is used to catalyse hybridization A combination of inhibition and catalysis will allow control of the bonds formed between elements of a self assembled structure We also demonstrate a new class of nanomachine made ...

Nanoscale Molecular Optoelectronics

Magnetoresistance of nanoscale molecular devices.

Affecting the current through a molecular or nanoscale junction is usually done by a combination of bias and gate voltages. Magnetic fields are less studied because nanodevices can capture only low values of the magnetic flux. We review recent work done with the aim of finding the conditions for magnetic fields to significantly affect the conductance of such junctions. The basic idea is to crea...