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Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
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Quantum coherence induces pulse shape modification in a semiconductor optical amplifier at room temperature.
Mirco Kolarczik1, Nina Owschimikow1, Julian Korn2
1Institut für Optik und Atomare Physik, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany.
Nature Communications
|December 17, 2013
Summary
Quantum-coherent effects in semiconductor quantum dots are observable at room temperature, even with rapid dephasing. This robust coherence, demonstrated by laser pulse reshaping, can be electrically controlled.
Area of Science:
- Quantum optics
- Condensed matter physics
- Semiconductor nanostructures
Background:
- Coherent light-matter interaction is crucial for controlling quantum states.
- Dephasing typically erases quantum coherence in condensed matter at room temperature.
Purpose of the Study:
- To demonstrate robust quantum-coherent effects in semiconductor quantum dots at room temperature.
- To investigate the influence of ultrafast dephasing on coherence.
- To explore electrical control over quantum coherence.
Main Methods:
- Analysis of ultrafast laser pulse reshaping during propagation through a semiconductor quantum dot amplifier.
- Utilizing electrical injection to adjust quantum dot population.
Main Results:
- Quantum-coherent effects were observed in semiconductor quantum dots at room temperature, despite ultrafast dephasing.
- Pulse modification during propagation serves as a signature of coherent light-matter interaction.
- Electrical control over quantum dot population effectively modulated the observed coherent effects.
Conclusions:
- Quantum coherence in suitably designed condensed matter systems can be robust enough for room-temperature observation.
- Ultrafast laser pulse reshaping is a viable method for detecting and analyzing coherent light-matter interactions.
- Electrical injection offers a pathway for controlling quantum-coherent phenomena in semiconductor nanostructures.
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