The most important law of radioactivity is that of the exponential decay. In the realm of quantum mechanics, however, this decay law is neither rigorous nor fundamental. The deviations from the exponential decay have been observed experimentally at the early stage of a decay process, but there is little evidence for nonexponential behavior at long times. Yet such long-term nonexponentiality is expected theoretically to probe the nonresonant background components of the initial wave function which preserve the structural interference and the memory of how the state was created. In this paper, we propose new observables that can be used for experimental investigations of the post-exponential decay regime, including the decay of threshold resonances, particle correlations in three-body decays, and interference between near-lying resonances. While the specific examples presented in this work pertain to atomic nuclei, the properties of nonexponential decay are generic, i.e., they apply to other many-body open quantum systems, such as hadrons, atoms, molecules, and nanostructures.The most important law of radioactivity is that of the exponential decay. In the realm of quantum mechanics, however, this decay law is neither rigorous nor fundamental. The deviations from the exponential decay have been observed experimentally at the early stage of a decay process, but there is little evidence for nonexponential behavior at long times. Yet such long-term nonexponentiality is expected theoretically to probe the nonresonant background components of the initial wave function which preserve the structural interference and the memory of how the state was created. In this paper, we propose new observables that can be used for experimental investigations of the post-exponential decay regime, including the decay of threshold resonances, particle correlations in three-body decays, and interference between near-lying resonances. While the specific examples presented in this work pertain to atomic nuclei, the properties of nonexponential decay are generic, i.e., they apply to other many-body open quantum systems, such as hadrons, atoms, molecules, and nanostructures.

arXiv:2211.11619Physical Review ResearchJun 23, 202328 citations

Exponential Decay in Quantum Mechanics

Vladimir I. Kruglov, Konstantin A. Makarov, B. S. Pavlov +1 more

Lecture notes in computer scienceJan 1, 20124 citations

Counter-factual carving exponentially improves entangled-state fidelity

Joshua Ramette, Josiah Sinclair, Vladan Vuletić

We propose a new method, "counter-factual" carving, that uses the "no-jump" evolution of a probe to generate entangled many-body states of high fidelity. The probe is coupled to a target ensemble of qubits and engineered to exponentially decay at a rate depending on the target collective spin, such that post-selecting on observing no probe decay precisely removes select faster-decaying spin components. When probe and $N$ -qubit target interact via a cavity mode of cooperativity $C$ , counter-factual carving generates entangled states with infidelities of $e^{-C/N}$ , an exponential improvement over previous carving schemes. Counter-factual carving can generate complex entangled states for applications in quantum metrology and quantum computing.We propose a new method, "counter-factual" carving, that uses the "no-jump" evolution of a probe to generate entangled many-body states of high fidelity. The probe is coupled to a target ensemble of qubits and engineered to exponentially decay at a rate depending on the target collective spin, such that post-selecting on observing no probe decay precisely removes select faster-decaying spin components. When probe and $N$-qubit target interact via a cavity mode of cooperativity $C$, counter-factual carving generates entangled states with infidelities of $e^{-C/N}$, an exponential improvement over previous carving schemes. Counter-factual carving can generate complex entangled states for applications in quantum metrology and quantum computing.

arXiv:2401.11407Jan 21, 20240 citations

QUANTUM–STATISTICAL DECAY

Series in modern condensed matter physicsMar 1, 19930 citations

Comment on the Quantum Foundations of Exponential Decay Law

Yasuo Yoshihuku

中部工業大学紀要 ADec 1, 19750 citations

Bound State Influence on Long-Time Non-Exponential Decay in Open Quantum Systems

Savannah Sterling Garmon

Get PDF Email Share Share with Facebook Tweet This Post on reddit Share with LinkedIn Add to CiteULike Add to Mendeley Add to BibSonomy Get Citation Copy Citation Text S. Garmon, "Bound State Influence on Long-Time Non-Exponential Decay in Open Quantum Systems," in The Rochester Conferences on Coherence and Quantum Optics and the Quantum Information and Measurement meeting, OSA Technical Digest (online) (Optica Publishing Group, 2013), paper M6.06. Export Citation BibTex Endnote (RIS) HTML Plain Text Citation alert Save articleGet PDF Email Share Share with Facebook Tweet This Post on reddit Share with LinkedIn Add to CiteULike Add to Mendeley Add to BibSonomy Get Citation Copy Citation Text S. Garmon, "Bound State Influence on Long-Time Non-Exponential Decay in Open Quantum Systems," in The Rochester Conferences on Coherence and Quantum Optics and the Quantum Information and Measurement meeting, OSA Technical Digest (online) (Optica Publishing Group, 2013), paper M6.06. Export Citation BibTex Endnote (RIS) HTML Plain Text Citation alert Save article

The Rochester Conferences on Coherence and Quantum Optics and the Quantum Information and Measurement meetingJan 1, 20132 citations

N

-qubit target interact via a cavity mode of cooperativity

C

, counter-factual carving generates entangled states with infidelities of

e^{-C/N}

, an exponential improvement over previous carving schemes. Counter-factual carving can generate complex entangled states for applications in quantum metrology and quantum computing.