Persistence of exponential decay for metastable quantum states at long times

Parrott, Robert E.; Lawrence, Jay

doi:10.1209/epl/i2002-00509-0

Cited by 19 publications

(15 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A particular case of this type density distribution is ω(ε) which can be found when one considers short-range potential models of quasi-stationary states: One can find such a density for finite-width barriers as well as delta barriers and with or without a potential inside the barier, etc. (see, eg., [15,16,17,20,21,22] and references one can find therein). In general in the models mentioned densities ω(ε) are proportional near E min to the square root of the energy ε,…”

Section: Final Remarksmentioning

confidence: 99%

General properties of the evolution of unstable states at long times

Urbanowski

2009

Eur. Phys. J. D

155

View full text Add to dashboard Cite

An effect generated by the nonexponential behavior of the survival amplitude of an unstable state at the long time region is considered. It is known that this amplitude tends to zero as t goes to the infinity more slowly than any exponential function of t. Using methods of asymptotic analysis we find the asymptotic form of this amplitude in the long time region in a general model independent case. We find that the long time behavior of this amplitude affects the form of the instantaneous energy of unstable states: This energy should be much smaller for suitably long times t than the energy of this state for t of the order of the lifetime of the considered unstable state.

show abstract

Section: Final Remarksmentioning

confidence: 99%

General properties of the evolution of unstable states at long times

Urbanowski

2009

Eur. Phys. J. D

155

View full text Add to dashboard Cite

show abstract

“…Whereas the relative turnover times are linked to the residual excited state density at the threshold, the decay exponents relate to the shape of the DOS [6,9,14]. Here, an exponent of ÿ4 is expected for Lorentzian-type excited state distributions, whereas ÿ2 indicates a Gaussian.…”

Section: Prl 96 163601 (2006) P H Y S I C a L R E V I E W L E T T E mentioning

confidence: 99%

Violation of the Exponential-Decay Law at Long Times

2006

View full text Add to dashboard Cite

The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro t purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. First-principles quantum mechanical calculations show that the exponential-decay law for any metastable state is only an approximation and predict an asymptotically algebraic contribution to the decay for sufficiently long times. In this Letter, we measure the luminescence decays of many dissolved organic materials after pulsed laser excitation over more than 20 lifetimes and obtain the first experimental proof of the turnover into the nonexponential decay regime. As theoretically expected, the strength of the nonexponential contributions scales with the energetic width of the excited state density distribution whereas the slope indicates the broadening mechanism.

show abstract

“…There have been many attempts to produce evidence of postexponential decay, with little success [5,6,7,8,9]. It has been argued that repetitive measurements on the same system, or simply the interaction with the environment would lead to persistence of the exponential regime to times well beyond those expected in an isolated system [2,10,11]. Nevertheless a recent measurement of transitions from exponential to post-exponential decay of excited organic molecules in solution [12] appears to contradict this expectation, and has triggered renewed interest in the topic.…”

Section: Introductionmentioning

confidence: 99%

Enhanced observability of quantum postexponential decay using distant detectors

Torrontegui¹,

Muga²,

Martorell³

et al. 2009

Phys. Rev. A

View full text Add to dashboard Cite

We study the elusive transition from exponential to post-exponential (algebraic) decay of the probability density of a quantum particle emitted by an exponentially decaying source, in one dimension. The main finding is that the probability density at the transition time, and thus its observability, increases with the distance of the detector from the source, up to a critical distance beyond which exponential decay is no longer observed. Solvable models provide explicit expressions for the dependence of the transition on resonance and observational parameters, facilitating the choice of optimal conditions.

show abstract

Persistence of exponential decay for metastable quantum states at long times

Cited by 19 publications

References 29 publications

General properties of the evolution of unstable states at long times

General properties of the evolution of unstable states at long times

Violation of the Exponential-Decay Law at Long Times

Enhanced observability of quantum postexponential decay using distant detectors

Contact Info

Product

Resources

About