Electrical resistance of Ni nanowires (diameter greater than or equal to 20 nm) near the Curie Temperatures

TL;DR

This study investigates electrical resistance in nickel nanowires with diameters as small as 20 nm near their Curie temperature, revealing persistent critical behavior and a transition towards quasi-one-dimensional spin systems.

Contribution

It provides new insights into the critical electrical behavior of ultra-thin nickel nanowires near T_C, highlighting the effects of reduced dimensions on magnetic phase transitions.

Findings

Critical behavior persists down to 20 nm diameter wires.

Suppression of resistivity critical exponents near T_C.

Approach to quasi-one-dimensional spin system.

Abstract

In this letter we report electrical transport measurements on nickel nanowires of diameters down to 20 nm in the region close to its paramagnetic-ferromagnetic transition temperature T_C (reduced temperature|t| less than or equal to 0.001). The data analysis done in the frame work of critical behavior of resistance near TC shows that the critical behavior persists even down to the lowest diameter wire of 20 nm. However, there is a suppression of the critical behavior of the resistivity as measured by the critical exponents and the parameters quantifying the anomaly. The spin system shows approach to a quasi one-dimensional spin system.