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Suppression of Multiphoton Resonances in Driven Quantum Systems via Pulse Shape Optimization
Denis Gagnon1,2, François Fillion-Gourdeau1,2, Joey Dumont1
1Université du Québec, INRS-Énergie, Matériaux et Télécommunications, Varennes, Québec, Canada, J3X 1S2.
Physical Review Letters
|September 27, 2017
Summary
Researchers control multiphoton absorption in systems like superconducting qubits by shaping laser pulses. This method suppresses unwanted transitions by manipulating the system
Area of Science:
- Quantum optics
- Strong-field physics
- Condensed matter physics
Background:
- Multiphoton absorption is crucial in quantum systems.
- Controlling these processes is key for applications in quantum computing and materials science.
- Driven two-level systems, such as superconducting qubits and laser-irradiated graphene, are important testbeds.
Purpose of the Study:
- To demonstrate precise control over multiphoton absorption.
- To suppress specific multiphoton resonances in driven two-level systems.
- To explore the underlying quantum mechanical mechanisms.
Main Methods:
- Utilizing Floquet theory for theoretical calculations.
- Employing differential evolution, an optimization algorithm, to tailor pulse shapes.
- Calculating Fourier coefficients of the driving function to achieve resonance suppression.
Main Results:
- Spectral shaping of the driving pulse effectively controls multiphoton absorption.
- Specific multiphoton resonances can be suppressed in the strong field regime.
- Transition probabilities are reduced by manipulating the system's Floquet states.
Conclusions:
- Coherent superposition of high-order Fourier harmonics is responsible for resonance suppression.
- This technique opens avenues for precise control in quantum technologies.
- The findings provide insights into strong-field quantum dynamics.
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