Abstract We study the symmetries of the static effective Hamiltonian of a driven superconducting nonlinear oscillator, the so-called squeeze-driven Kerr Hamiltonian, and discover a remarkable quasi-spin symmetrysu(2) at integer values of the ratio of the detuning parameter Δ to the Kerr coefficientK. We investigate the stability of this newly discovered symmetry to high-order perturbations arising from the static effective expansion of the driven Hamiltonian. Our finding may find applications in the generation and stabilization of states useful for quantum computing. Finally, we discuss other Hamiltonians with similar properties and within reach of current technologies.
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Effective versus Floquet theory for the Kerr parametric oscillator
Parametric gates and processes engineered from the perspective of the static effective Hamiltonian of a driven system are central to quantum technology. However, the perturbative expansions used to derive static effective models may not be able to efficiently capture all the relevant physics of the original system. In this work, we investigate the conditions for the validity of the usual low-order static effective Hamiltonian used to describe a Kerr oscillator under a squeezing drive. This system is of fundamental and technological interest. In particular, it has been used to stabilize Schrödinger cat states, which have applications for quantum computing. We compare the states and energies of the effective static Hamiltonian with the exact Floquet states and quasi-energies of the driven system and determine the parameter regime where the two descriptions agree. Our work brings to light the physics that is left out by ordinary static effective treatments and that can be explored by state-of-the-art experiments.
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- Award ID(s):
- 2124511
- PAR ID:
- 10544872
- Publisher / Repository:
- Quantum
- Date Published:
- Journal Name:
- Quantum
- Volume:
- 8
- ISSN:
- 2521-327X
- Page Range / eLocation ID:
- 1298
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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