Monolithically integrated single quantum dots coupled to bowtie nanoantennas.

Area of Science:

• Quantum photonics
• Plasmonics
• Nanotechnology

Background:

• Developing chip-scale quantum photonic technologies requires integrating semiconductor quantum emitters with plasmonic nanodevices.
• Stable, bright semiconductor emitters operating in the telecommunication band and compatible with CMOS technology are essential.

Purpose of the Study:

• To demonstrate enhanced light-matter coupling between single quantum dots and plasmonic nanoantennas.
• To investigate the impact of nanoantennas on quantum dot emission intensity, spontaneous emission rate, and polarization.

Main Methods:

• Monolithic integration of near-surface Indium Arsenide (InAs) quantum dots with sub-wavelength metal nanoantennas.
• Characterization of enhanced emission intensity, Purcell factor, and polarization of coupled quantum dots.

Main Results:

• Achieved up to ~16x enhancement in single quantum dot emission intensity.
• Observed up to 3.4x Purcell enhancement in spontaneous emission rate.
• Demonstrated strong emission polarization along the antenna axis, reaching up to ~85% linear polarization.

Conclusions:

• Unambiguously demonstrated strong coupling between individual quantum dots and nanoantennas.
• This integration is crucial for advancing nanoscale quantum photonic devices.
• Opens new avenues for quantum plasmonic sensors, photovoltaic devices, quantum light sources, and nano-lasers.