Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review Letters

Entanglement between a Photon and a Quantum Well

W. Hoyer, M. Kira, Stephan W. Koch, H. Stolz, Sorin Mosor, Julian Sweet, Claudia Ell, G. Khitrova, H. M. Gibbs

Published Aug 3, 2004• 18 citations
Publisher

Abstract

The lack of translational invariance perpendicular to the plane of a single quantum well causes equal probability for spontaneous emission to the left or right. Combining one emission path from the left and one from the right into a common detector leads to interference fringes for fundamentally indistinguishable paths corresponding to geometries where the same in-plane momentum is transferred to the quantum well. For all other paths, no interference is observed because of the entanglement between the photon and extended Bloch states of the many-body system. In multiple-quantum-well structures the interference can be controlled via the spacing between the wells.

DOI
10.1103/physrevlett.93.067401

Related papers

Cascaded Quantum Well Structure Emitting Entangled Multiphoton States

Amir Sivan, Meir Orenstein

Deterministic cascaded quantum well source spontaneously emits inter-entangled triple frequency multiphoton states. The entanglement stems from interference of indistinguishable quantum evolution paths in the cascaded coupled quantum wells. Novel controllable quantum entanglement and quantum error detection are two possible features of the multiphoton source.

IEEE Photonics Conference•Nov 12, 2023•0 citations

Two-photon interference from disparate quantum sources

Glenn S. Solomon, Edward B. Flagg, Sergey Polakov +3 more

When photons emitted from different sources are indistinguishable they will interfere when brought together on a beam splitter. Using quantum dots and parametric down conversion, we manipulate dissimilar quantum sources to produce mutually indistinguishable photons.

The Rochester Conferences on Coherence and Quantum Optics and the Quantum Information and Measurement meeting•Jan 1, 2013•0 citations

Fluorescence control through multiple interference mechanisms

Emmanuel Paspalakis, Christoph H. Keitel, P. L. Knight

We discuss the spontaneous emission from a coherently prepared and microwave-driven doublet of potentially closely spaced excited states to a common ground level. Multiple interference mechanisms are identified that may lead to fluorescence inhibition in well-separated regions of the spectrum or act jointly in canceling the spontaneous emission. In addition to phase-independent quantum interferences due to combined absorptions and emissions of driving field photons, we distinguish two competing phase-dependent interference mechanisms as means of controlling the fluorescence. The indistinguishable quantum paths may involve the spontaneous emission from the same state of the doublet, originating from the two different components of the initial coherent superposition. Alternatively the paths involve a different spontaneous photon from each of two decaying states, necessarily with the same polarization. This makes these photons indistinguishable in principle within the uncertainty of the two decay rates. The phase dependence arises for both mechanisms because the interfering paths differ by an unequal number of stimulated absorptions and emissions of the microwave field photons.

arXiv:quant-ph/9810072•Physical Review A•Dec 1, 1998•128 citations

Spontaneous emission from correlated emitters

Offek Tziperman, Gefen Baranes, Alexey A. Gorlach +5 more

We find the quantum state of light emitted from a many-body system of entangled emitters, presenting examples for cavity and waveguide QED. Squeezed and Schrodinger-cat states can be created by controlling emitter locations and interactions.

Frontiers in Optics•Jan 1, 2023•1 citation

Controllable on-chip generation and detection of path-entangled microwave photons

Y. F. Li, De He, S. R. He +1 more

Path-entangled optical photons have played an important role in the multinode quantum network and quantum sensing, although most of them were usually generated probabilistically with linear optical platforms. Here, by using the spontaneous radiations of a pair of entangled solid-state qubits coupled to a common one-dimensional waveguide, we alternatively propose an on-chip approach to deterministically generate the path-entangled microwave single-photon state. With the trapped electrons on liquid helium, we specifically demonstrate its feasibility. In addition to the calculation of the von Neumann entropy for the entanglement witness, we show that the generated path-entanglement photons can be experimentally tested by simply measuring the distinguishability of the spontaneously emitted spectra of the photons being detected by the left and right single-photon detectors. The generalization of the proposal to the other solid-state experimental platforms is also discussed.

Physical Review A•Jan 21, 2025•0 citations

Saving the Unruh signal: Coherent cancellation of spontaneous emission with entangled detectors

Arash Azizi

The Unruh effect is notoriously difficult to detect, as it is exponentially overwhelmed by Wigner--Weisskopf spontaneous emission. We show that this fundamental obstacle can be overcome by harnessing multi-detector quantum interference. By preparing a system of three entangled Unruh--DeWitt detectors in a specific W-state, the spontaneous emission channels can be forced to destructively interfere and vanish, thereby "saving" the Unruh signal by coherently silencing this dominant noise. Our central result is the derivation of the condition for complete and simultaneous cancellation of all right- and left-traveling emission modes. We find this requires preparing the detectors in a unique entangled state whose real-valued coefficients are fixed by an elegant geometric constraint, given by a ratio of sines of the logarithms of the detector accelerations. This work establishes multi-detector entanglement as a precision tool for noise cancellation in relativistic quantum settings, offering a new pathway toward the definitive observation of the Unruh signal.

arXiv:2601.02490•Physical review. D/Physical review. D.•Dec 22, 2025•0 citations
The lack of translational invariance perpendicular to the plane of a single quantum well causes equal probability for spontaneous emission to the left or right. Combining one emission path from the left and one from the right into a common detector leads to interference fringes for fundamentally indistinguishable paths corresponding to geometries where the same in-plane momentum is transferred to the quantum well. For all other paths, no interference is observed because of the entanglement between the photon and extended Bloch states of the many-body system. In multiple-quantum-well structures the interference can be controlled via the spacing between the wells.
We discuss the spontaneous emission from a coherently prepared and microwave-driven doublet of potentially closely spaced excited states to a common ground level. Multiple interference mechanisms are identified that may lead to fluorescence inhibition in well-separated regions of the spectrum or act jointly in canceling the spontaneous emission. In addition to phase-independent quantum interferences due to combined absorptions and emissions of driving field photons, we distinguish two competing phase-dependent interference mechanisms as means of controlling the fluorescence. The indistinguishable quantum paths may involve the spontaneous emission from the same state of the doublet, originating from the two different components of the initial coherent superposition. Alternatively the paths involve a different spontaneous photon from each of two decaying states, necessarily with the same polarization. This makes these photons indistinguishable in principle within the uncertainty of the two decay rates. The phase dependence arises for both mechanisms because the interfering paths differ by an unequal number of stimulated absorptions and emissions of the microwave field photons.
Path-entangled optical photons have played an important role in the multinode quantum network and quantum sensing, although most of them were usually generated probabilistically with linear optical platforms. Here, by using the spontaneous radiations of a pair of entangled solid-state qubits coupled to a common one-dimensional waveguide, we alternatively propose an on-chip approach to deterministically generate the path-entangled microwave single-photon state. With the trapped electrons on liquid helium, we specifically demonstrate its feasibility. In addition to the calculation of the von Neumann entropy for the entanglement witness, we show that the generated path-entanglement photons can be experimentally tested by simply measuring the distinguishability of the spontaneously emitted spectra of the photons being detected by the left and right single-photon detectors. The generalization of the proposal to the other solid-state experimental platforms is also discussed.
The Unruh effect is notoriously difficult to detect, as it is exponentially overwhelmed by Wigner--Weisskopf spontaneous emission. We show that this fundamental obstacle can be overcome by harnessing multi-detector quantum interference. By preparing a system of three entangled Unruh--DeWitt detectors in a specific W-state, the spontaneous emission channels can be forced to destructively interfere and vanish, thereby "saving" the Unruh signal by coherently silencing this dominant noise. Our central result is the derivation of the condition for complete and simultaneous cancellation of all right- and left-traveling emission modes. We find this requires preparing the detectors in a unique entangled state whose real-valued coefficients are fixed by an elegant geometric constraint, given by a ratio of sines of the logarithms of the detector accelerations. This work establishes multi-detector entanglement as a precision tool for noise cancellation in relativistic quantum settings, offering a new pathway toward the definitive observation of the Unruh signal.