Energetics of Microwaves Probed by Double Quantum Dot Absorption

Area of Science:

• Quantum physics
• Mesoscopic systems
• Quantum optics

Background:

• Photon-assisted tunneling in quantum dots is crucial for quantum information processing.
• Understanding microwave interactions with quantum systems is key to developing new technologies.
• The photoelectric effect provides a foundational model for light-matter interactions.

Purpose of the Study:

• To investigate the energy dynamics of microwave interactions with a double quantum dot photodiode.
• To demonstrate wave-particle duality in photon-assisted tunneling under microwave irradiation.
• To establish a microwave analog of the photoelectric effect for studying quantum dot energetics.

Main Methods:

• Utilizing a double quantum dot photodiode system.
• Applying microwave radiation across different drive limits (weak and strong).
• Performing stopping-potential measurements and analyzing detuning conditions.

Main Results:

• Single-photon energy dictates absorption in the weak-drive limit.
• Microwave wave amplitude determines energy scale in the strong-drive limit, inducing bias triangles.
• The fine-structure constant defines the transition threshold between these regimes.

Conclusions:

• Microwave-driven quantum dots exhibit energy absorption behaviors analogous to the photoelectric effect.
• The study elucidates the wave-particle duality in photon-assisted tunneling.
• Control over quantum dot energetics can be achieved through microwave field manipulation.