Low-energy Charge Dynamics in La 0.7 Ca 0.3 Mno 3 Typeset Using Revt E X
نویسندگان
چکیده
Direct experimental estimations of the low-energy (1.5∼10 meV) complex dielectric constants spectrum and its temperature variation have been investigated for La 0.7 Ca 0.3 MnO 3 thin films using terahertz time-domain spec-troscopy. At low temperatures, a clear Drude-term emerges. With increasing temperature, the scattering rate increases, while the plasma frequency decreases, derived both from a simple Drude model. Finally, a Drude-term submerges well below the insulator-metal transition temperature. Low-energy charge dynamics is discussed on the basis of the present results.
منابع مشابه
Evidence of Magnetization-dependent Polaron Formation in Typeset Using Revt E X
X-ray-absorption fine-structure measurements at the Mn K-edge as a function of temperature were performed on samples of La 1−x Ca x MnO 3 and La 0.67 Pb 0.33 MnO 3. All samples have a metal-insulator (MI) transition near the ferromagnetic transition, except the Ca 0.5 sample, which does not have a MI transition. Near T c for the MI samples, the Debye-Waller σ 2 for the Mn-O atom-pair increases ...
متن کاملElectroresistance and electronic phase separation in mixed-valent manganites.
The sensitivity of transport in colossal magnetoresistance (CMR) manganites to external electric and magnetic fields is examined using field effect configurations with La(0.7)Ca(0.3)MnO(3) (LCMO), Na(0.7)Sr(0.3)MnO(3), La(0.7)Ba(0.3)MnO(3), and La(0.5)Ca(0.5)MnO(3) (0.5-doped LCMO) channels, and ferroelectric PbZr(0.2)Ti(0.8)O(3) (PZT) or dielectric (SrTiO(3)) gates. A large electroresistance (...
متن کاملLow-temperature Electrical Transport and Double Exchange in Typeset Using Revt E X
The resistivity in the ferromagnetic state of flux-grown La 2/3 (Pb,Ca) 1/3 MnO 3 single crystals, measured in magnetic fields up to 7 T, reveals a strong quadratic temperature dependence at and above 50 K. At lower temperatures , this contribution drops precipitously leaving the resistivity essentially temperature independent below 20 K. The Seebeck coefficient also reflects a change of behavi...
متن کاملNonlinear transport in nanoscale phase separated colossal magnetoresistive oxide thin films
transport in nanoscale phase separated colossal magnetoresistive oxide thin films" (2014). Preparation of rare-earth manganite-oxide thin films by metalorganic aerosol deposition technique Appl. We report a study of the I-V characteristics of 2.5–5.4 nm epitaxial La 1Àx Sr x MnO 3 (x ¼ 0.33 and 0.5) and La 0.7 Ca 0.3 MnO 3 thin films. While La 0.67 Sr 0.33 MnO 3 films exhibit linear conduction ...
متن کاملLow-energy Interaction of a Cosmic String and an Extreme Dilatonic Black Hole Typeset Using Revt E X
The interaction of a cosmic string and a maximally charged dilatonic black hole is studied in the low-velocity limit. In particular, the string-black hole scattering at a low velocity is investigated.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2000