@article { ISI:000253283700034,
	title = {Chemical inhomogeneity and mixed-state ferromagnetism in diluted magnetic semiconductor Co : TiO2},
	journal = {Chemistry of Materials},
	volume = {20},
	number = {4},
	year = {2008},
	month = {FEB},
	pages = {1344-1352},
	publisher = {AMER CHEMICAL SOC},
	type = {Article},
	address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},
	abstract = {<p>Diluted magnetic semiconductors (DMS) are among the most intensely investigated materials in recent times in view of their great application potential. Yet, they are also the most controversial because of the possibility of extrinsic effects attributable to dopant solubility and clustering, point defects, incorporation of unintentional impurities, etc. This has highlighted the central role of materials chemistry in rendering a specific microstate and property response. In this work, we provide a combined window of high-resolution scanning transmission electron microscopy and electron energy-loss spectrometry, X-ray absorption (XAS)/X-ray magnetic circular dichroism (XMCD), and magnetization measurements on epitaxial rutile CoxTi1-xO2 (x = 0-0.06) system (the first discovered oxide-DMS, which continues to be controversial) grown at low temperature (400 degrees C) under different ambient atmospheres. The study brings out a mixed-state scenario of ferromagnetism involving intrinsic DMS (uniform dopant distribution at low dopant concentration) and coupled cluster magnetism, involving cobalt associations within the matrix at higher concentrations. We also show that by matrix valence control during growth, it is possible to realize a uniform embedded cluster state and the related coupled cluster magnetism.</p>},
	issn = {0897-4756},
	doi = {10.1021/cm702089z},
	author = {Ogale, Satishchandra B. and Kundaliya, Darshan and Mehraeen, Shareghe and Fu, Lian-feng and Zhang, Shixiong and Lussier, Alexandre and Dvorak, Joe and Browning, Nigel D. and Idzerda, Yves and Venkatesan, Thirumalai}
}
@article { ISI:000267509500004,
	title = {Electronic manifestation of cation-vacancy-induced magnetic moments in a transparent oxide semiconductor: anatase Nb:TiO2},
	journal = {Advanced Materials},
	volume = {21},
	number = {22},
	year = {2009},
	month = {JUN},
	pages = {2282+},
	publisher = {WILEY-V C H VERLAG GMBH},
	type = {Article},
	address = {BOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANY},
	abstract = {<p>Nb-doped anatase TiO2 thin films grown by pulsed-laser deposition show Kondo scattering in elctronic-transport measurements, providing evidence for the formation of magnetic moments. The origin of magnetism is attributed to cation (Ti) vacancies, confirmed by X-ray absorption spectroscopy and first-principle calculations. The Ti vacancies are controlled by oxygen partial pressure during growth.</p>},
	issn = {0935-9648},
	doi = {10.1002/adma.200803019},
	author = {Zhang, Shixiong and Ogale, Satishchandra B. and Yu, Weiqiang and Gao, Xingyu and Liu, Tao and Ghosh, Saurabh and Das, Gour P. and Wee, Andrew T. S. and Greene, Richard L. and Venkatesan, Thirumalai}
}
