# Hot Electrons Regain Coherence in Semiconducting Nanowires

## TL;DR

This paper demonstrates that hot electrons in semiconducting nanowires unexpectedly regain phase coherence at higher energies, challenging prior assumptions about decoherence in one-dimensional systems, with implications for quantum technology.

## Contribution

It reveals the non-monotonic energy dependence of hot-electron decoherence and visualizes this phenomenon using scanning tunneling microscopy, supported by a theoretical model.

## Key findings

- Hot electrons regain coherence at high energies.
- Visualization of electron interference patterns in nanowires.
- Non-monotonic relaxation behavior explained by electron interactions.

## Abstract

The higher the energy of a particle is above equilibrium the faster it relaxes due to the growing phase-space of available electronic states it can interact with. In the relaxation process phase coherence is lost, thus limiting high energy quantum control and manipulation. In one-dimensional systems high relaxation rates are expected to destabilize electronic quasiparticles. We show here that the decoherence induced by relaxation of hot electrons in one-dimensional semiconducting nanowires evolves non-monotonically with energy such that above a certain threshold hot-electrons regain stability with increasing energy. We directly observe this phenomenon by visualizing for the first time the interference patterns of the quasi-one-dimensional electrons using scanning tunneling microscopy. We visualize both the phase coherence length of the one-dimensional electrons, as well as their phase coherence time, captured by crystallographic Fabry-Perot resonators. A remarkable agreement with a theoretical model reveals that the non-monotonic behavior is driven by the unique manner in which one dimensional hot-electrons interact with the cold electrons occupying the Fermi-sea. This newly discovered relaxation profile suggests a high-energy regime for operating quantum applications that necessitate extended coherence or long thermalization times, and may stabilize electronic quasiparticles in one dimension.