Energetics of Microwaves Probed by Double Quantum Dot Absorption
Subhomoy Haldar, Harald Havir, Waqar Khan, Sebastian Lehmann, Claes Thelander, Kimberly A. Dick, V. F. Maisi
Abstract
We explore the energetics of microwaves interacting with a double quantum dot photodiode and show wave-particle aspects in photon-assisted tunneling. The experiments show that the single-photon energy sets the relevant absorption energy in a weak-drive limit, which contrasts the strong-drive limit where the wave amplitude determines the relevant-energy scale and opens up microwave-induced bias triangles. The threshold condition between these two regimes is set by the fine-structure constant of the system. The energetics are determined here with the detuning conditions of the double dot system and stopping-potential measurements that constitute a microwave version of the photoelectric effect.