Abstract: A method for preparing a poled structure forms a ferroelectric substrate with a first polarization direction, wherein the ferroelectric substrate has a first surface and a second surface. An electrode-patterning process is then performed to form a first electrode structure on the first surface, and the first electrode structure includes a plurality of active blocks and a plurality of passive blocks, wherein at least one passive block is sandwiched between two active blocks. Subsequently, a poling process is performed including applying a predetermined voltage to the active blocks and floating the passive blocks such that a current such as a leakage current or a tunnel current is generated from the active blocks to the passive blocks to form a plurality of inverted domains with a second polarization direction in the ferroelectric substrate.

Abstract: A method for preparing a periodically poled structure comprises the steps of providing a ferroelectric substrate having an upper surface and a bottom surface, forming an upper electrode including at least one first block and at least one second block on the upper surface, forming a bottom electrode including at least one third block and at least one fourth block on the bottom surface and performing a plurality of poling processes to form at least one first domain and at least one second domain in the ferroelectric substrate, wherein the first domain is formed between the first block and the third block, and the second domain is formed between the second block and the fourth block.

Abstract: A method for preparing a periodically poled structure comprises the steps of providing a ferroelectric substrate having an upper surface and a bottom surface, forming an upper electrode including at least one first block and at least one second block on the upper surface, forming a bottom electrode including at least one third block and at least one fourth block on the bottom surface and performing a plurality of poling processes to form at least one first domain and at least one second domain in the ferroelectric substrate, wherein the first domain is formed between the first block and the third block, and the second domain is formed between the second block and the fourth block.

Abstract: Chemical vapor deposition (CVD) is used to synthesize single-wall carbon nanotubes by a catalytic reaction, and a method of preparing the catalyst is also provided. A transition metal catalyzing growth of carbon nanotubes, an oxide of a precursor metal preventing agglomeration of catalyst particles, and a precious metal are essentially consisted in the catalyst. The catalyst particles can be further dispersed by quasi-explosive effect occurred when the oxidized precious metal is reduced.

Abstract: Chemical vapor deposition (CVD) is used to synthesize single-wall carbon nanotubes by a catalytic reaction, and a method of preparing the catalyst is also provided. A transition metal catalyzing growth of carbon nanotubes, an oxide of a precursor metal preventing agglomeration of catalyst particles, and a precious metal are essentially consisted in the catalyst. The catalyst particles can be further dispersed by quasi-explosive effect occurred when the oxidized precious metal is reduced.

Abstract: Chemical vapor deposition (CVD) is used to synthesize single-wall carbon nanotubes by a catalytic reaction, and a method of preparing the catalyst is also provided. A transition metal catalyzing growth of carbon nanotubes, an oxide of a precursor metal preventing agglomeration of catalyst particles, and a precious metal are essentially consisted in the catalyst. The catalyst particles can be further dispersed by quasi-explosive effect occurred when the oxidized precious metal is reduced.

Abstract: A method for preparing a periodically poled structure comprises the steps of applying a predetermined voltage to first conductive blocks on a ferroelectric substrate such that a plurality of first domains having a first polarization direction are formed in the ferroelectric substrate and applying the predetermined voltage to second conductive blocks on the ferroelectric substrate such that a plurality of second domains having the first polarization direction are formed in the ferroelectric substrate between the first domains. In addition, the method may further comprises a step of applying the predetermined voltage to a third conductive blocks between the first conductive blocks and the second conductive blocks such that a plurality of third domains having the first polarization direction are formed in the ferroelectric substrate between the first domains and the second domains.