As one example, LPCMO is chosen as a representative model system

As one example, LPCMO is chosen as a representative model system due to its sub-micrometer scale phase separation that can be easily accessed by conventional lithographic fabrication processes. It is found that by reducing a single-crystal LPCMO thin film to a wire with a width comparable to a scale on the order of the inherent EPS, the system exhibits ultrasharp jumps in resistivity, as shown in Figure  4 [27]. These jumps are attributed to a reduction of selleck chemicals llc the transport lanes to a single channel. As the insulating barriers of the charge-ordered state are broken by the reduction of temperature or an selleck compound increase

in magnetic field, the resistance in the wire shows sharp jumps around the MIT, which reflects the nature of the first-order phase transition between ferromagnetic metal and charge-ordered insulator domains. Since the transport measurement EPZ015666 can reveal the signature of phase transition of an individual EPS domain in a manganite wire, it becomes possible to probe the EPS domain dynamics

of manganites. This is accomplished by setting an LPCMO wire at or very near the critical point of phase transition and measuring the phase fluctuation with high-time resolution. The very limited number of EPS domains that can be hosted in the wire effectively removes the problems associated with spatial averaging methods in the conventional transport measurements while allowing for a high temporal resolution. At the critical point of the MIT, single-domain fluctuations will show a clear signature in time-dependent resistivity measurements, as shown in Figure  5 [29]. In Figure  5a, the resistivity (ρ) of a 10 μm × 50 μm × 70 nm LPCMO wire under a

3.75-T magnetic field exhibits an ultrasharp jump at the MIT centered at 83 K. This is contrasted with the same sample in a film geometry (Figure  5a, inset) which shows a smooth transition from metallic to insulating behavior across a 150-K window. The extremely Amisulpride large jump in the resistivity of the wire results solely from its geometry’s ability to remove the effects of spatial averaging in transport measurements. By setting the temperature of the LPCMO wire precisely in the middle of the 2-K window found in the temperature-dependent resistivity scan, it is possible to study the microscopic details of the transition in both space and time. Figure  5b shows the time-dependent resistivity while the wire is held at the transition temperature. It is clear that the apparent two-state system with resistivity jumps is actually comprised of a much richer multistate system. There are three inherent resistivity levels, each containing a further two-state fluctuation.

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