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arXiv · 1803.05189

Band Structure Dynamics in Indium Wires

M. Chávez-Cervantes·R. Krause·S. Aeschlimann·I. Gierz
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Abstract

One-dimensional Indium wires grown on Si(111) substrates, which are metallic at high temperatures, become insulating below $\sim100$ K due to the formation of a Charge Density Wave (CDW). The physics of this transition is not conventional and involves a multiband Peierls instability with strong interband coupling. This CDW ground state is readily destroyed with femtosecond laser pulses resulting in a light-induced insulator-to-metal phase transition. The current understanding of this transition remains incomplete, requiring measurements of the transient electronic structure to complement previous investigations of the lattice dynamics. Time- and angle-resolved photo\-emission spectroscopy with extreme ultra-violet radiation is applied to this end. We find that the transition from the insulating to the metallic band structure occurs within $\sim660$ fs that is a fraction of the amplitude mode period. The long life time of the transient state ($>100$ ps) is attributed to trapping in a metastable state in accordance with previous work.

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M. Chávez-Cervantes, R. Krause, S. Aeschlimann, I. Gierz. 2018-04-21. Band Structure Dynamics in Indium Wires. https://doi.org/10.1103/physrevb.97.201401

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