Post-processing of real-time quantum event measurements for an optimal bandwidth

Area of Science:

• Quantum physics
• Solid-state physics
• Nanotechnology

Background:

• Single electron tunneling is crucial for quantum devices.
• Traditional charge detectors require extreme conditions (mK temperatures, advanced lithography).
• Optical transitions offer a promising alternative for detecting tunneling events.

Purpose of the Study:

• Investigate optical detection of single electron tunneling using resonance fluorescence from quantum dots.
• Evaluate the achievable bandwidth and time resolution of this optical detection method.
• Compare post-processing analysis with traditional real-time charge detection.

Main Methods:

• Utilized low-temperature resonance fluorescence from a self-assembled quantum dot in a diode.
• Detected single photons in real-time.
• Employed post-processing techniques to analyze recorded photon data and extract electron transport signals.
• Analyzed waiting-time distributions and full-counting statistics.

Main Results:

• Demonstrated real-time single-photon detection from a quantum dot.
• Successfully extracted electron transport signals via post-processing.
• Achieved analysis bandwidths as high as 175 kHz.
• Identified post-processing as key to optimizing time resolution.

Conclusions:

• Optical detection via quantum dot fluorescence is a viable, high-bandwidth alternative to traditional charge detectors.
• Post-processing of photon data allows for flexible optimization of time resolution.
• Future work can potentially achieve time resolutions exceeding 1 MHz.