  This letter reports on the observation of optoelectronic switching in
addressable molecular crossbar junctions fabricated using polymer
stamp-printing method. The active medium in the junction is a molecular
self-assembled monolayer softly sandwiched between gold electrodes. The
molecular junctions are investigated through currentvoltage measurements at
varied temperature (from 95 to 300 K) in high vacuum condition. The junctions
show reversible optoelectronic switching with the highest on/off ratio of 3
orders of magnitude at 95 K. The switching behavior is independent of both
optical wavelength and molecular structure, while it strongly depends on the
temperature. Initial analysis indicates that the distinct binding nature of the
molecule/electrode interfaces play a dominant role in the switching
performance.
