Nanodomain Engineering in Ferroelectric Crystals Using High Voltage Atomic Force Microscopy

摘要: Reversal of the spontaneous polarization direction under an applied electric field is a basic property ferroelectrics. However traditional techniques used for fabrication domain gratings have been able to produce domains not smaller then 2 µm. Sub-micron and nanometer scale may be fabricated using atomic force microscopy based techniques; however, date there was no success in fabricating stable that elongate without widening throughout thick A breakthrough emerged with recent development high voltage microscope has enabled us obtain sub-micrometer configurations bulk ferroelectric crystals. comprehensive experimental theoretical description nanodomain engineering on presented. It found string-like are formed due super-high tip. The domains, which resemble channels electrical breakdown, nucleate around 107 V/cm at surface, grow crystal where external practically zero. theory explaining shape shows driving breakdown decrease total free energy system increasing length. tailoring two-dimensional strip-like nanodomains 250 micron RbTiOPO4 single Studying influence voltage, tip velocity strips allowed fabricate (with width 590 nm) useful backward-propagating quasi-phase-matched frequency conversion. Some important aspects structure characterization presented discussed. In last sections we show amplitude contrast contact AFM imaging mode largely affected by difference work functions antiparallel domains. shown direct measurement piezoelectric coefficient can performed microscope.