The ability to grow and manipulate nanowires opens an opportunity for study of various effects of the reduced dimensions on the physical properties of matter, including (but not limited to) quantum effects.  For example, one of the  new interesting aspects of these small structures is their increased surface to volume ratio, i.e., more atoms are defined as surface atoms. Surface behaves differently than bulk, and thus understanding the physics of surfaces becomes crucial for applications of these structures. The following image exemplifies how the reduction of nanowire size and the closure of surface affects the recombination path of photoexcited charge carriers.

[see Phys. Rev. B 69, 245401 (2004)  cited over 150 times]