Nonlinear electric transport and switching phenomenon in the mixed-stack charge-transfer crystal tetrathiafulvalene-<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>p</mml:mi></mml:math>-chloranil

Abstract

A remarkable nonlinearity and a switching effect have been observed for electric transport in a tetrathiafulvalene (TTF)-$p$-chloranil crystal. Experimental evidence indicates that these features are of an intrinsic origin associated with the neutral-ionic transition. A possible mechanism is discussed in terms of field-dependent low-energy excitations, such as solitons and neutral-ionic domain walls, which are inherent to the quasi-one-dimensional donor-acceptor stacks in the TTF-$p$-chloranil crystal.