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Updated: Jun 4, 2026
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Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
Published on: October 13, 2017
Strong coupling between two quantum dots and a photonic crystal cavity using magnetic field tuning
Hyochul Kim1, Deepak Sridharan, Thomas C Shen
1Department of Electrical and Computer Engineering, IREAP, University of Maryland, College Park, Maryland 20742, USA and Joint Quantum Institute, University of Maryland, College Park, Maryland 20742, USA.
Optics Express
|March 4, 2011
Summary
Researchers used magnetic fields to tune two indium arsenide quantum dots (QDs) to a photonic crystal cavity, achieving strong coupling. This method enhanced vacuum Rabi splitting (VRS) through collective QD behavior, agreeing with theoretical models.
Area of Science:
- Quantum optics
- Solid-state physics
- Nanotechnology
Background:
- Quantum dots (QDs) are crucial for quantum information processing.
- Achieving strong coupling between QDs and optical cavities is essential for enhanced light-matter interactions.
- Precise frequency tuning of QDs is challenging but necessary for resonant coupling.
Purpose of the Study:
- To demonstrate strong coupling between two indium arsenide (InAs) quantum dots and a photonic crystal cavity.
- To utilize a magnetic field as a novel frequency tuning method for simultaneous QD-cavity resonance.
- To investigate the impact of simultaneous QD coupling on vacuum Rabi splitting (VRS).
Main Methods:
- Employing a magnetic field to tune the exciton spin states of two InAs QDs.
- Achieving simultaneous resonance of QDs with a photonic crystal cavity, even with large detunings (up to 1.35 meV).
- Measuring VRS for individual and simultaneous QD-cavity coupling scenarios.
Main Results:
- Demonstrated precise frequency matching of two InAs QDs to a cavity resonance using magnetic fields up to 7 T.
- Observed enhanced VRS when two QDs were simultaneously coupled to the cavity, indicating collective behavior.
- Experimental results showed excellent agreement with theoretical calculations using the full master equation.
Conclusions:
- Magnetic field tuning is an effective method for achieving strong coupling between multiple QDs and optical cavities.
- Simultaneous coupling of QDs leads to collective oscillator strength and enhanced light-matter interactions (VRS).
- The findings provide a pathway for developing advanced quantum devices utilizing coupled quantum dots.
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