Physical Origin of Transient Negative Capacitance in a Ferroelectric Capacitor

Abstract

Transient negative differential capacitance (NC), the dynamic reversal of transient capacitance in an electrical circuit is of highly technological and scientific interest since it probes the foundation of ferroelectricity. In this letter, we study a resistor-ferroelectric capacitor (R-FeC) network through a series of coupled equations based on Kirchhoff's law, Electrostatics, and Landau theory. We show that transient NC in a R-FeC circuit originates from the mismatch between rate of free charge change on the metal plate and that of bound charge change in a ferroelectric (FE) capacitor during polarization switching. This transient charge dynamic mismatch is driven by the negative curvature of the FE free energy landscape. It is also analytically shown that a free energy profile with the negative curvature is the only physical system that can describe transient NC during the two-state switching in a FE capacitor. Furthermore, this transient charge dynamic mismatch is justified by the dependence of external resistance and intrinsic FE viscosity coefficient. The depolarization effect on FE capacitors also shows the importance of negative curvature to transient NC. The relation between transient NC and negative curvature provides a direct insight into the free energy landscape during the FE switching.

arXiv comment5 pages, 11 figures

References in corpus (4)

• Domain Switching Kinetics in Disordered Ferroelectric Thin Films
• Effect of a built-in electric field in asymmetric ferroelectric tunnel junctions
• Theoretical Approach to Electroresistance in Ferroelectric Tunnel Junctions
• A Thermodynamic Perspective of Negative-capacitance Field-effect-transistors

Cited by in corpus (8)

• A Critical Review of Recent Progress on Negative Capacitance Field-Effect Transistors
• A Thermodynamic Perspective of Negative-capacitance Field-effect-transistors
• Domain Wall Acceleration by Ultrafast Field Application: An Ab Initio-Based Molecular Dynamics Study
• Inversion Charge-boost and Transient Steep-slope induced by Free charge-polarization Mismatch in a Ferroelectric-metal-oxide-semiconductor Capacitor
• Sub-60 mV/decade switching in a metal-insulator-metal-insulator-semiconductor transistor without ferroelectric component
• Physical Mechanism behind the Hysteresis-free Negative Capacitance Effect in Metal-Ferroelectric-Insulator-Metal Capacitors with Dielectric Leakage and Interfacial Trapped Charges
• Dual mechanisms for transient capacitance anomaly in improper ferroelectrics
• Thermodynamic driving force of transient negative capacitance of ferroelectric capacitors