2013 Fiscal Year Final Research Report

Mgnetic domain analysis using terahertz waves

Research Project

Project/Area Number	24656207
Research Category	Grant-in-Aid for Challenging Exploratory Research
Allocation Type	Single-year Grants
Research Field	Electronic materials/Electric materials
Research Institution	Osaka University
Principal Investigator	KAWAYAMA Iwao 大阪大学, レーザーエネルギー学研究センタ, 准教授 (10332264)
Project Period (FY)	2012-04-01 – 2014-03-31
Keywords	テラヘルツ / 酸化物薄膜 / 強磁性薄膜 / 電荷密度波
Research Abstract	Low-energy charge dynamics in PSMO (110) epitaxial film were investigated along and across two dissimilar in-plane orthogonal axes, [1-10] and [001], by recording the complex refractive index in the energy range of 1 - 7 meV. We report a novel observation of a gradual crossover from Drude-like metallic conductivity to charge-density-wave (CDW) like collective excitations as the polarized terahertz excitation field is swept across the orthogonal in-plane axes. This is a rare manifestation of a CDW mode in a highly conducting stripe-type charge-ordered (CO) system, which is fundamentally different from the CDW modes of checkerboard CO. Interestingly, the contrasting charge dynamics along orthogonal in-plane axes form an intrinsic electronic switch, apparently a consequence of the unique CO of PSMO.

(2 results)