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Related papers: Spontaneous Emission from a Fractal Vacuum

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This paper discusses two distinct, but related issues in quantum fluctuation effects. The first is the frequency spectrum which can be assigned to one loop quantum processes. The formal spectrum is a flat one, but the finite quantum effects…

Quantum Physics · Physics 2008-11-26 L. H. Ford

Eigenstate multifractality is of significant interest with potential applications in various fields of quantum physics. Most of the previous studies concentrated on fine-tuned quantum models to realize multifractality which is generally…

Disordered Systems and Neural Networks · Physics 2025-07-03 Adway Kumar Das , Anandamohan Ghosh , Ivan M. Khaymovich

We consider a two-level quantum system (qubit) which is continuously measured by a detector and calculate the spectral density of the detector output. In the weakly coupled case the spectrum exhibits a moderate peak at the frequency of…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Alexander N. Korotkov

Detection of a single photon escaping an optical cavity QED system prepares a non-classical state of the electromagnetic field. The evolution of the state can be modified by changing the drive of the cavity. For the appropriate feedback,…

Quantum Physics · Physics 2009-11-07 W. P. Smith , J. E. Reiner , L. A. Orozco , S. Kuhr , H. M. Wiseman

The decoherence effect due to emission of gravitons is examined. It shows the same qualitative features of the QED effect which has already been investigated, it is obviously much weaker, wholly universal and shows a stronger energy…

Quantum Physics · Physics 2009-11-10 Giorgio Calucci

Deterministic emitters transform electronic excitations to photons with unity efficiency. Their development is crucial for both energy-efficient optical interconnects and photonic quantum technologies, but neither rigorous theoretical…

Quantum Physics · Physics 2025-04-28 Sergei Lepeshov , Søren Stobbe

The spectrum of vacuum fluctuations of the electromagnetic field is determined solely from first physical principles and can be seen as a fundamental property that qualifies as a primary radiation standard. We demonstrate that the amplitude…

Quantum Physics · Physics 2019-06-26 Samuel Lemieux , Enno Giese , Robert Fickler , Maria V. Chekhova , Robert W. Boyd

We investigate the problem of metric fluctuations in the presence of the vacuum fluctuations of matter fields and critically assess the usual assertion that vacuum energy implies a Planckian cosmological constant. A new stochastic classical…

General Relativity and Quantum Cosmology · Physics 2008-06-19 Charles H. -T. Wang , Paolo M. Bonifacio , Robert Bingham , J. Tito Mendonca

Despite growing interest, there is a scarcity of known predictions in the regime where both quantum and general relativistic effects become observable. Here, we investigate a combined atom-field system in a curved spacetime, with a specific…

Quantum Physics · Physics 2026-03-24 Jerzy Paczos , Navdeep Arya , Sofia Qvarfort , Daniel Braun , Magdalena Zych

In the context of quantum field theories in curved spacetime, we compute the effective action of the transition amplitude from vacuum to vacuum in the presence of an external gravitational field. The imaginary part of resulted effective…

High Energy Physics - Theory · Physics 2009-11-07 She-Sheng Xue

A quantum dipole interacting with an optical cavity is one of the key models in cavity quantum electrodynamics (cavity-QED). To treat this system theoretically, the typical approach is to truncate the dipole to two levels. However, it has…

We describe the emission, detection and structure of multiphoton states of light. We include the effect of frequency filtering, which describes, at a fundamental level, physical detection of a quantum emitter. The case of the spontaneous…

Spontaneous emission of an atom (molecule) placed near a nanocylinder of elliptical cross-section of an arbitrary composition is studied. The analytical expressions have been obtained for the radiative and nonradiative channels of…

Optics · Physics 2009-11-13 D. V. Guzatov , V. V. Klimov

In this paper I discuss the formation of topological defects in quantum field theory and the relation between fractals and coherent states. The study of defect formation is particularly useful in the understanding of the same mathematical…

High Energy Physics - Theory · Physics 2008-08-22 Giuseppe Vitiello

Collective spontaneous emission occurs when multiple quantum emitters decay into common radiation modes, resulting in enhanced or suppressed emission. Here, we find the quantum state of light collectively emitted from emitters exhibiting…

Spontaneous emission can create coherences in a multilevel atom having close lying levels, subject to the condition that the atomic dipole matrix elements are non-orthogonal. This condition is rarely met in atomic systems. We report the…

Quantum Physics · Physics 2009-10-31 Anil K. Patnaik , G. S. Agarwal

We investigate the effect of a waveguide on an emitter spontaneous emission in its vicinity. The impact of various possible orientations of an emitter with respect to the waveguide surface is studied through simulations and compared with…

In the present work we use the Li\'enard-Wiechert potential to show that very violent fluctuations are experienced by an electromagnetic charged extended particle when it is perturbed from its rest state. The feedback interaction of…

Quantum Physics · Physics 2020-06-15 Álvaro G. López

Waveguide quantum electrodynamics (QED) provides a powerful framework for engineering quantum interactions, traditionally relying on periodic photonic arrays with continuous energy bands. Here, we investigate waveguide QED in a…

Quantum Physics · Physics 2026-04-27 Florian Bönsel , Flore K. Kunst , Federico Roccati

A localized charged particle oscillating near a reflecting boundary is considered as a model for non-cancellation of vacuum fluctuations. Although the mean velocity of the particle is sinusoidal, the velocity variance produced by vacuum…

Quantum Physics · Physics 2011-12-06 Victor Parkinson , L. H. Ford