Towards Addressable Molecular Devices

This remarkable molecular memory was preceded by two other related examples of addressable molecular electronics from the Stoddart and Heath groups in collaboration with Hewlett-Packard scientists. First in 1999 a [2]rotaxane based system was configured into molecular AND and OR logic gates, then in 2000 a [2]catenane based molecular switch was reported. The molecular basis for the operation of this switch is the same as in 11.67, namely reorientation in response to reduction of 

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In order to get die discussion of specific problems under way, I returned to an issue that was discussed after one of the morning lectures given that in our drive towards miniaturization we may eventually be able to build nanoscopic devices in which individual molecules perform functions that are currendy performed by the elements of microelectronic or optoelectronic circuits or additional functions that we are presendy not able to perform, how shall we address the individual molecules and connect them to the outside world At times, this has been declared inqxissible, and much criticism has been leveled at the whole so far non-existent field of molecular electronics as a result. 

Although this article addresses general aspects of microworld control, the primary emphasis is towards molecular or chemical control. It was pointed out in the introduction that the field of microworld control has broadened out to encompass a variety of other applications of equal significance. This list includes the creation of quantum computers, controlled solid-state electronics, atom lasers, novel quantum electronic devices and optical materials, as well as possibly other applications. Each of these subjects has its own community of scientists, and unfortunately, there has been little interaction between the groups involved. Some of these communities are actually larger than those involved in chemical reaction control efforts. For example, a quantum... 

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