Electric-field and current-induced metastability and resistivity relaxation in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mi mathvariant="normal">La</mml:mi><mml:mn>0.8</mml:mn></mml:msub><mml:msub><mml:mi mathvariant="normal">Ca</mml:mi><mml:mn>0.2</mml:mn></mml:msub><mml:mi mathvariant="normal">Mn</mml:mi><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mn>3</mml:mn></mml:msub></mml:mrow></mml:math>at low temperatures

Low frequency noise in current biased La 0.82 Ca 0.18 MnO 3 single crystals has been investigated in a wide temperature range from 79 K to 290 K. Despite pronounced changes in magnetic properties and dissipation mechanisms of the sample with changing temperature, the noise spectra were found to be always of the 1/f type and their intensity (except the lowest temperature studied) scaled as a square of the bias. At liquid nitrogen temperatures and under bias exceeding some threshold value, the behavior of the noise deviates from the quasi-equilibrium modulation noise and starts to depend in a non monotonic way on bias. It has been verified that the observed noise obeys Dutta and Horn model of 1/f noise in solids. The appearance of nonequilibrium 1/f noise and its dependence on bias have been associated with changes in the distribution of activation energies in the underlying energy landscape. These changes have been correlated with bias induced changes in the intrinsic tunneling mechanism dominating dissipation in La 0.82 Ca 0.18 MnO 3 at low temperatures.

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“…17,31 Our first experiments have confirmed this assumption and their analysis will be published elsewhere.…”

Section: Discussionsupporting

confidence: 65%

Bias dependent 1/f conductivity fluctuations in low-doped La1−xCaxMnO3 manganite single crystals

Belogolovskii

Jung

Markovich

et al. 2011

Journal of Applied Physics

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“…very attractive explanation. Nevertheless, one has to remember that a very similar behavior of the resistivity has been also observed in slightly less doped LCMO crystals with x = 0.18 and x = 0.2, 6,36 in which the structural J-T transition occurs solely in the paramagnetic phase, T JT > T C . 2 We have associated the domain rotation with the structural J-T transition.…”

Section: 13supporting

confidence: 56%

“…13,36 With an exception of the rotation of an easy magnetization axis, remarkably less pronounced than in x = 0.2 sample, and very slight frequency dependence of the ac susceptibility, all cluster glass transition signatures are practically absent in x = 0.22 LCMO crystals. very attractive explanation.…”

Section: 13mentioning

confidence: 91%

Ferromagnetic domain structure ofLa0.78Ca0.22MnO3single crystals

et al. 2005

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The magneto-optical technique has been employed to observe spontaneous ferromagnetic domain structures in La 0.78 Ca 0.22 MnO 3 single crystals. The magnetic domain topology was found to be correlated with the intrinsic twin structure of the investigated crystals. With decreasing temperature the regular network of ferromagnetic domains undergoes significant changes resulting in apparent rotation of the domain walls in the temperature range of 70-150 K. The apparent rotation of the domain walls can be understood in terms of the Jahn-Teller deformation of the orthorhombic unit cell, accompanied by additional twinning.

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“…Metastable states [46] and a variety of other hysteretic and time-dependent effects have been observed [18,34]. This current regime is quite different to the one used in the experiments reported here.…”

Section: =mentioning

confidence: 37%

“…Others have made studies of this compound excited by large current [18,34,46]. Metastable states [46] and a variety of other hysteretic and time-dependent effects have been observed [18,34].…”

Section: =mentioning

confidence: 99%

Metal-insulator transition and electroresistance in lanthanum/calcium manganites La1-xCa x MnO3 (x= 0–0.5) from voltage-current-temperature surfaces

2008

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Of the perovskites, ABX 3 , a subset of special interest is the family in which the A site is occupied by a lanthanide ion, the B site by a transition metal and X is oxygen, as such materials often exhibit a large change in electrical resistance in a magnetic field, a phenomenon known as "colossal" magnetoresistance (MR). Two additional phenomena in this family have also drawn attention: the metal-insulator transition (MIT) and electroresistance (ER). The MIT is revealed by measuring resistance as a function of temperature, and observing a change in the sign of the gradient. ER -the dependence of the resistance on applied current -is revealed by measuring resistance as a function of applied current. Up until now, the phenomena of MIT and ER have been treated separately. Here we report simultaneous observation of the MIT and ER in the lanthanum/calcium manganites. We accomplish this by measuring voltage-current curves over a wide temperature range (10-300 K) allowing us to build up an experimental voltage surface over current-temperature axes. These data directly lead to resistance surfaces. This approach provides additional insight into the phenomena of electrical transport in the lanthanum/calcium manganites, in particular the close connection of the maximum ER to the occurrence of the MIT in those cases of a paramagnetic insulator (PMI) to ferromagnetic metal (FMM) transition.

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Electric-field and current-induced metastability and resistivity relaxation inLa0.8Ca0.2MnO3at low temperatures

Cited by 63 publications

References 36 publications

Bias dependent 1/f conductivity fluctuations in low-doped La1−xCaxMnO3 manganite single crystals

Bias dependent 1/f conductivity fluctuations in low-doped La1−xCaxMnO3 manganite single crystals

Ferromagnetic domain structure ofLa0.78Ca0.22MnO3single crystals

Metal-insulator transition and electroresistance in lanthanum/calcium manganites La1-xCa x MnO3 (x= 0–0.5) from voltage-current-temperature surfaces

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