Electron wavefunction probing in room-temperature semiconductors: direct observation of Rabi oscillations and self-induced transparency

TL;DR

This paper reports the first direct observation of quantum coherent effects, including Rabi oscillations and self-induced transparency, in a room-temperature semiconductor, demonstrating potential for practical quantum devices.

Contribution

It presents the first direct electronic wavefunction probing at room temperature in a semiconductor, using ultrafast techniques to observe quantum effects typically seen only at cryogenic temperatures.

Findings

Observation of Rabi oscillations at room temperature

Detection of self-induced transparency in a semiconductor laser amplifier

Demonstration of quantum effects in solid-state devices at practical temperatures

Abstract

Quantum coherent light-matter interactions have been at the forefront of scientific interest since the fundamental predictions of Einstein and the later work of Rabi. Direct observation of quantum coherent interactions entails probing the electronic wavefunction which requires that the electronic state of the matter does not de-phase during the measurement, a condition that can be satisfied by lengthening the coherence time or by shortening the observation time. The short de-phasing time in semiconductors has dictated that all coherent effects reported to date have been recorded directly only at cryogenic temperatures. Here we report on the first direct electronic wavefunction probing in a room-temperature semiconductor. Employing an ultrafast characterization scheme we have demonstrated Rabi oscillations and self-induced transparency in an electrically driven, room-temperature semiconductor laser amplifier, revealing the most intimate details of the light-matter interactions seen to date. The ability to employ quantum effects in solid-state media, which operate at elevated temperatures, will finally bring true quantum mechanical concepts into the realm of practical devices.