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Double Quantum Dot Floquet Gain Medium



Jacob M. Taylor, Michael Gullans, Jason Petta, J. Stehlik, Yinyiu Liu, Christopher Eichler, T Hartke, X Mi


A qubit coupled to a microwave resonator allows the study of fundamental light-matter interactions at the level of single photons1. The paradigm of circuit quantum electrodynam- ics (cQED) enables the generation of classical and non-classical light2–5 . When qubits are strongly driven, intriguing quantum effects emerge, including Landau-Zener-Stuckelberg interference6,7 , lasing without inversion8 and vacuum squeezing9,10. Joining superconducting resonators and semiconductors – in the form of double quantum dots (DQD) – provides a versatile, electrically tunable quantum system that interacts strongly with light4,11,12 . Here we show that a single electron in a periodi- cally driven DQD functions as a “Floquet gain medium,” where population imbalances in the DQD Floquet quasi-energy levels lead to an intricate pattern of gain and loss features in the cavity response6,7,13. We further measure a large intra-cavity photon number nc in the absence of a cavity drive field, due to equilibration in the Floquet picture14,15. Our device operates in the absence of a dc current – one and the same electron is repeatedly driven to the excited state to generate population inversion. These results pave the way to future studies of non-classical light and thermalization of driven systems.
Physical Review X


Quantum dots, maser, Floquet, circuit QED


Taylor, J. , Gullans, M. , Petta, J. , Stehlik, J. , Liu, Y. , Eichler, C. , Hartke, T. and Mi, X. (2016), Double Quantum Dot Floquet Gain Medium, Physical Review X, [online], (Accessed June 24, 2024)


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Created November 7, 2016, Updated November 10, 2018