Sensing Very Weak Strains at the Single-Molecule Scale

Single-molecule solvation-shell sensing.

We present a new route to single-molecule sensing via solvation shells surrounding a current-carrying backbone molecule. As an example, we show that the presence of a water solvation shell "gates" the conductance of a family of oligothiophene-containing molecular wires, and that the longer the oligothiophene, the larger is the effect. For the longest example studied, the molecular conductance i...

Single molecule sensing with carbon nanotube devices

Nanoscale electronic devices like field-effect transistors have long promised to provide sensitive, label-free detection of biomolecules. In particular, single-walled carbon nanotubes have the requisite sensitivity to detect single molecule events and sufficient bandwidth to directly monitor single molecule dynamics in real time. Recent measurements have demonstrated this premise by monitoring ...

Anomalous Baryogenesis at the Weak Scale*

One of the fundamenta1 constants of nature is the baryon asymmetry of the universe the ratio of the number of baryons to the entropy. This constant is about lol1 . In baryon-number conserving theories, this was just an initial condition. With the advent of grand unified theories (GUTS), baryon number is no longer conserved, and this asymmetry can be generated dynamically. Unfortunately, however...

Single Molecule Dynamics at Surfaces

Mass action at the single-molecule level.

We developed a system to reversibly encapsulate small numbers of molecules in an array of nanofabricated "dimples". This system enables highly parallel, long-term, and attachment-free studies of molecular dynamics via single-molecule fluorescence. In studies of bimolecular reactions of small numbers of confined molecules, we see phenomena that, while expected from basic statistical mechanics, a...