User:Dr farhan saif



In 2006 a new type of microscope called Recurrence Tracking Microscope(RTM) was presented. It is based on quantum recurrence phenomena. It probe surfaces having nano-structures with atomic size resolution.

Basic principles
To begin the experiment a cloud of atoms is trapped and cooled in a magneto optical trap (MOT). This MOT is then moved near to the evanescent wave atomic mirror. Trapped atoms are then drooped above the evanescent wave atomic mirror from a little hight. The mirror for the atoms is due to the total internal reflection of the incident laser light field from the surface of the dielectric film. This creates an evanescent wave field above the surface. This reflecting surface is connected to a cantilever which has its other end linked with the surface having nano structure. So change in position of cantilever gives rise to change in quantum recurrence time which can be easily measured.

Advantages
Recurrence Tracking Microscope has many advantages over existing techniques of STM and AFM as it can probes material surfaces regardless of its kind, it can be a conductor or insulator. Impurities in nano-structure surfaces has no effects on its performance, while the old technique has in some cases. As in some old techniques impurity atoms in the surface gives a false results of extra surface structures. Another advantage is the dynamical operational mode which provides information about the surface having periodicity.