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arXiv · 0704.3923

Unusual doping and temperature dependence of photoemission spectra from manganites

Prabuddha Sanyal·Subhra Sen Gupta·Nandan Pakhira·H. R. Krishnamurthy·D. D. Sarma·T. V. Ramakrishnan
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Abstract

A recent, major, puzzle in the core-level photoemission spectra of doped manganites is the observation of a 1-2 eV wide shoulder with intensity varying with temperature T as the square of the magnetization over a T scale of order 200K, an order of magnitude less than electronic energies. This is addressed and resolved here, by extending a recently proposed two electron fluid l-b model for these systems to include core-hole effects. The shoulder arises from a rapid redistribution of e_g electron density, as a function of T, between the highly localized (l) and band-like (b) states. Furthermore, our theory leads to a correspondence between spectral changes due to increasing doping and decreasing T, as experimentally observed.

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Prabuddha Sanyal, Subhra Sen Gupta, Nandan Pakhira, H. R. Krishnamurthy, D. D. Sarma, T. V. Ramakrishnan. 2007-04-30. Unusual doping and temperature dependence of photoemission spectra from manganites. https://doi.org/10.1209/0295-5075/82/47010

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