R&D: Enhanced Ferroelectric Polarization in Epitaxial Superconducting–Ferroelectric Heterostructure Thin Films for NVM Cell

AIP Advances has published an article written by Ravikant, CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi 110012, India, Academy of Scientific and Innovative Research (AcSIR), CSIR-National Physical Laboratory Campus, Dr. K. S. Krishnan Road, New Delhi 110012, India, and Department of Physics, Government College Sailana, Vikram University, Ujjain 457550, India, Charanjeet Singh,CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi 110012, India, and Academy of Scientific and Innovative Research (AcSIR), CSIR-National Physical Laboratory Campus, Dr. K. S. Krishnan Road, New Delhi 110012, India, Anjali Panchwanee,UGC-DAE, Consortium for Scientific Research, Khandwa Road, Indore 452001, India, Rajib K. Rakshit, Manju Singh,CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi 110012, India, and Academy of Scientific and Innovative Research (AcSIR), CSIR-National Physical Laboratory Campus, Dr. K. S. Krishnan Road, New Delhi 110012, India, V. R. Reddy, Ram Janay Choudhary,UGC-DAE, Consortium for Scientific Research, Khandwa Road, Indore 452001, India, V. N. Ojha, and Ashok Kumar, CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi 110012, India, and Academy of Scientific and Innovative Research (AcSIR), CSIR-National Physical Laboratory Campus, Dr. K. S. Krishnan Road, New Delhi 110012, India.

Abstract: “We report the growth and polarization switching properties of epitaxial ferroelectric–superconducting heterostructure PbZr_0.52Ti_0.48O₃ (PZT) (100 nm)/YBa₂Cu₃O_7−δ (YBCO) (100 nm) thin films for non-volatile ferroelectric random access memory elements. The epitaxial nature of the heterostructure is verified using the reciprocal space mapping data with the superconducting phase transition temperature (T_c) of nearly 25 K far below the T_c of as-grown YBCO under the same condition. The significant remanent polarization (P_r) ∼45µC/cm² at 1 kHz can switch from one state to another using 1μs pulse. The devices meet the basic criteria of memory elements, such as high resistance ∼10 GΩ at 8 V, a butterfly-like capacitance–voltage (C/V) loop, significant polarization, a sharp change in the displacement current, long-time charge retention, and small fatigue at room temperature.“