SearcharxivSearch

arXiv subjects

Ulrich Poppe

Publications and source records attributed to Ulrich Poppe.

2 recordsLinked to original sources

Variable resistor made by repeated steps of epitaxial deposition and lithographic structuring of oxide layers by using wet chemical etchants

Variable resistors were constructed from epitaxial SrRuO3 (SRO), La0.67Sr0.33MnO3 (LSMO) and SrTiO3 layers with perovskite crystal structure. Each layer was patterned separately by lithographic methods. Optimized wet chemical etchants and several polishing steps in organic solvents allowed good epitaxy of subsequent layers, comparable to epitaxy on pristine substrates. Periodate as the oxidizing agent for SRO and iodide with ascorbic acid as the reducing agents for LSMO were used to attack these chemically resistant oxides. The final devices changed their conductance in a similar manner to previously described variable resistors that were defined with shadow masks.

cond-mat.mtrl-sci

Non-volatile gated variable resistor based on doped La_{2}CuO_{4} and SrTiO_{3} heterostructures

Gated variable resistors were manufactured by depositing epitaxial heterostructures of doped La_{2}CuO_{4} and SrTiO_{3} layers. Their conductance change as function of write current I and write time t followed a simple empirical law of the form ΔG/G = CI^A t^B. This behavior is in agreement with ionic transport that accelerates exponentially with electrical field strength.

cond-mat.mtrl-sci