Anisotropic thermochemical hole burning phenomenon on TTF-TCNQ single crystal

A remarkable anisotropic thermochemical hole burning (THB) phenomenon was observed on TTF-TCNQ charge-transfer complex when using a STM tip to write information bits on its single-crystal surface. Such an anisotropy of hole formation was found to be closely related to the anisotropic thermal conducting property of TTF-TCNQ crystal, strongly supporting a nanometer scale thermochemical reaction mechanism. The high thermal conductivity of TTF-TCNQ leads to a very weak dependence of hole size on the pulse duration within a certain time scale, which was never observed with ammonium-TCNQ complexes. Comparative studies using isotropic thermal conducting TEA(TCNQ)2 complex and theoretical analyses were performed for elucidating the unique hole burning properties of TTF-TCNQ complex. The thermal gravimetry combined with mass spectrometry (TG-MS) of TTF-TCNQ was also done for a detailed understanding of the thermochernical decomposition reaction.