Spontaneous decay of artificial atoms in a multi-qubit system

Abstract

We consider a one-dimensional chain of N equidistantly spaced noninteracting qubits embedded in an open waveguide. In the frame of single-excitation subspace, we systematically study the evolution of qubits amplitudes if the only qubit in the chain was initially excited. We show that the temporal dynamics of qubits amplitudes crucially depend on the value of kd, where k is the wave vector, d is a distance between neighbor qubits. If kd is equal to an integer multiple of $\pi$, then the qubits are excited to a stationary level which scales as SN^{-1}S. We show that in this case, it is the dark states which prevent qubits from decaying to zero even though they do not contribute to the output spectrum of photon emission. For other values of kd the excitations of qubits have the form of damping oscillations, which represent the vacuum Rabi oscillations in a multi-qubit system. In this case, the output spectrum of photon radiation is defined by a subradiant state with the smallest width.

arXiv comment22 pages, 12 figures, 17 references

References in corpus (13)

• Microwave photonics with superconducting quantum circuits
• Resonance Fluorescence of a Single Artificial Atom
• Photon-mediated interactions between distant artificial atoms
• Biorthogonal Quantum Mechanics
• The Single-Photon Router
• Strongly interacting photons in one-dimensional continuum
• Cavity QED with atomic mirrors
• Theory of Subradiant States of a One-Dimensional Two-Level Atom Chain
• Subradiant states of quantum bits coupled to a one-dimensional waveguide
• Multiphoton transitions in Josephson-junction qubits (Review Article)
• Waveguide bandgap N-qubit array with a tunable transparency resonance
• Signal amplification in a qubit-resonator system
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