Achieving dynamic manipulation and control of single molecules at high spatio-temporal resolution is pivotal for advancing atomic-scale computing and nanorobotics. However, this endeavour is critically challenged by complex nature of atomic and molecular interactions, high-dimensional characteristics of nanoscale systems, and scarcity of experimental data. Here, we present a toy model for controlling single-molecule diffusion by harnessing electrostatic forces arising from elementary surface charges within a lattice structure, mimicking embedded charges on a surface. We investigate the interplay between quantum mechanics and electrostatic interactions in single molecule diffusion processes using a combination of state-dependent diffusion equations and Green's functions. We find that surface charge density critically influences diffusion coefficients, exhibiting linear scaling akin to Coulombic forces. We achieve accurate predictions of experimental diffusion constants and extending the observed range to values reaching up to 6000
μm2ms−1 and 80000
μm2ms−1. The molecular trajectories predicted by our model bear resemblance to planetary motion, particularly in their gravity-assisted acceleration-like behaviour. It holds transformative implications for nanorobotics, motion control at the nanoscale, and computing applications, particularly in the areas of molecular and quantum computing where the trapping of atoms and molecules is essential. Beyond the state-of-the-art optical lattice and scanning tunnelling microscopy for atomic/molecular manipulation, our findings give unambiguous advantage of precise control over single-molecule dynamics through quantum manipulation at the angstrom scale.
Ultracold single molecules have wide-ranging potential applications, such as ultracold chemistry, precision measurements, quantum simulation, and quantum computation. However, given the difficulty of achieving full control of a complex atom-molecule system, the coherent formation of single molecules remains a challenge. Here, we report an alternative route to coherently bind two atoms into a weakly bound molecule at megahertz levels by coupling atomic spins to their two-body relative motion in a strongly focused laser with inherent polarization gradients. The coherent nature is demonstrated by long-lived atom-molecule Rabi oscillations. We further manipulate the motional levels of the molecules and measure the binding energy precisely. This work opens the door to full control of all degrees of freedom in atom-molecule systems.
Recent work done at Stanford in the manipulation of atoms and particles is summarized. Techniques to further increase our control of neutral particles such as atomic fountains, funnels, and trampolines have been demonstrated. These techniques are now being combined with a new type of velocity selection in order to study atom/surface interactions and to improve the limit on the charge neutrality of atoms. Trapping techniques have also allowed us to manipulate single molecules of DNA in aqueous solution while observing the molecules in fluorescence.