Optical detection of single nano-objects by transient absorption microscopy.

In recent years there has been considerable effort in developing ultra-sensitive imaging techniques based on absorption. This mini-review describes recent results from our laboratory on detecting single nano-objects using transient absorption microscopy. This technique is extremely flexible, allowing the detection of single semiconductor and metal nanostructures with high sensitivity. The goal of this review is to illustrate key points in implementing transient absorption microscopy for ultra-sensitive detection, as well as to discuss the advantages and disadvantages of this technique compared to other optical absorption based methods.