Converse-piezoelectric effect on current-voltage characteristics of symmetric ferroelectric tunnel junctions

Current-voltage characteristics of symmetric ferroelectric tunnel junction were studied in an ultrathin ferroelectric barrier with the consideration of the thickness and strain dependent converse-piezoelectric effect. With proper boundary conditions, large piezoelectric strain can be achieved in the ferroelectric barrier when its thickness is in the vicinity of the critical thickness. Because of the exponential relationship between the tunneling current and the effective film thickness, tunneling current can be greatly enhanced by the external electric field and substrate induced strain. (C) 2012 American Institute of Physics. [doi:10.1063/1.3673600]