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 A

Parity-dependent photon-subtracted two-mode squeezed vacuum states

Ananga Mohan Datta, Andrea Blanco‐Redondo, Kurt Busch, Armando Perez-Leija

Published Jul 8, 2025• 4 citations
Publisher

Abstract

The removal of photons from certain quantum light sources produces so-called photon-subtracted states with enhanced mean photon numbers and intricate quantum correlations. Here, we propose an integrated photon-subtraction scheme that, contrary to previous approaches, is not heralded by photon correlation (coincidence) measurements. In this way, our technique exploits the “Welcher Weg” (“which way”) information problem, as it does not provide information about the modes from which the subtracted photons emanated. We show that this lack of information allows the generation of multiphoton states endowed with rich quantum correlations that strongly depend on the parity, evenness or oddness, of the number of subtracted photons.

DOI
10.1103/4x83-y4bg

Related papers

Odd and even photon-subtracted two-mode squeezed vacuum states

A. Datta, Kurt Busch, Armando Pérez-Leija

Photon-subtracted two-mode squeezed vacuum states, a significant quantum resource, exhibit intricate correlations and unique quantum properties. In this work, we propose a theoretical yet experimentally feasible model to engineer these states using a waveguide trimer. Our study uncovers distinct characteristics of the photon-subtracted state depending on whether an even or odd number of photons is extracted, shedding light on the subtle relationship between quantum state manipulation and the parity of the number of subtracted photons. Furthermore, our integrated device facilitates the generation of multiphoton states with tunable correlations, offering significant potential for applications in quantum-enhanced technologies.

arXiv:2412.07397•Dec 10, 2024•0 citations

Multiphoton quantum-state engineering using conditional measurements

Omar S. Magaña‐Loaiza, Roberto de J. León‐Montiel, Armando Pérez-Leija +7 more

Abstract The quantum theory of electromagnetic radiation predicts characteristic statistical fluctuations for light sources as diverse as sunlight, laser radiation, and molecule fluorescence. Indeed, these underlying statistical fluctuations of light are associated with the fundamental physical processes behind their generation. In this contribution, we experimentally demonstrate that the manipulation of the quantum electromagnetic fluctuations of two-mode squeezed vacuum states leads to a family of quantum-correlated multiphoton states with tunable mean photon numbers and degree of correlation. Our technique relies on the use of conditional measurements to engineer the excitation mode of the field through the simultaneous subtraction of photons from two-mode squeezed vacuum states. The experimental generation of nonclassical multiphoton states by means of photon subtraction unveils novel mechanisms to control fundamental properties of light. As a remarkable example, we demonstrate the engineering of a quantum state of light with up to ten photons, exhibiting nearly Poissonian photon statistics, that constitutes an important step towards the generation of entangled lasers. Our technique enables a robust protocol to prepare quantum states with multiple photons in high-dimensional spaces and, as such, it constitutes a novel platform for exploring quantum phenomena in mesoscopic systems.

arXiv:1901.00122•npj Quantum Information•Sep 27, 2019•96 citations

Photon-subtracted two-mode squeezed vacuum states and applications to quantum optical interferometry

Raul Carranza, Christopher C. Gerry

We study the application of photon-subtracted two-mode squeezed vacuum states (TMSVS), where identical photon numbers are subtracted from each beam, to the problem of quantum optical interferometry with the photon-number parity measurements scheme. Previously, Anisimov et al. [Phys. Rev. Lett.104, 103602 (2010)] have studied the prospect of using the TMSVS for parity measurements based interferometry. However, the joint photon number distribution of this state before beam splitting is thermal-like in each mode, meaning that its statistics are super-Poissonian and that the most probable state of the field is the double vacuum and that the average photon number is low. Furthermore, with these states the sensitivity of the phase-shift measurement is extremely sensitive to the size of the phase shift to be measured for large average photon numbers. The simultaneous subtraction of 1, 2, or 3 photons from each mode has the effects of increasing the average photon numbers of each mode and rendering the statistics nearly Poissonian and in some cases sub-Poissonian. We show that phase uncertainties for such states are less sensitive to the phase shift itself at large average photon numbers. We also show that the photon-subtracted TMSVS also lead to increased resolution.

Journal of the Optical Society of America B•Aug 30, 2012•108 citations

Theory of Photon Subtraction for Two-Mode Entangled Light Beams

Oscar Rosas-Ortiz, Kevin Zelaya

Photon subtraction is useful to produce nonclassical states of light addressed to applications in photonic quantum technologies. After a very accelerated development, this technique makes possible obtaining either single photons or optical cats on demand. However, it lacks theoretical formulation enabling precise predictions for the produced fields. Based on the representation generated by the two-mode SU(2) coherent states, we introduce a model of entangled light beams leading to the subtraction of photons in one of the modes, conditioned to the detection of any photon in the other mode. We show that photon subtraction does not produce nonclassical fields from classical fields. It is also derived a compact expression for the output field from which the calculation of conditional probabilities is straightforward for any input state. Examples include the analysis of squeezed-vacuum and odd-squeezed states. We also show that injecting optical cats into a beam splitter gives rise to entangled states in the Bell representation.

arXiv:2108.12528•Quantum Reports•Sep 3, 2021•3 citations

Four-photon subtraction from picosecond squeezed vacuum demonstrating Wigner negativity without loss correction

Mamoru Endo, Takefumi Nomura, Tatsuki Sonoyama +12 more

Multiphoton subtraction from a traveling squeezed vacuum is a standard route to non-Gaussian optical-state engineering. High state-generation rates call for ultrashort optical pulses driven by high-repetition-rate lasers, but combining higher-order subtraction with ultrashort pulsed light and full state reconstruction remains challenging. Here we demonstrate up to four-photon subtraction from 10-ps squeezed-vacuum wave packets generated by a broadband waveguide optical parametric amplifier. Using a Ti-Au transition-edge sensor for photon-number-resolved heralding and homodyne tomography on the signal mode, we reconstruct the generated states up to the four-photon-subtracted case. The reconstructed states exhibit clear parity-dependent structure and visible Wigner-function negativity without loss correction. These results extend the experimentally accessible regime of multiphoton subtraction in broadband traveling optical modes and establish a platform for non-Gaussian optical resource-state engineering in continuous-variable quantum optics.

arXiv:2502.08952•Physical Review A•Jul 13, 2026•4 citations

Quantum optical interferometry via general photon-subtracted two-mode squeezed states*

Li-Li Hou, Jianzhong Xue, Yongxing Sui +1 more

We investigate the sensitivity of phase estimation in a Mach–Zehnder interferometer with photon-subtracted two-mode squeezed vacuum states. Our results show that, for given initial squeezing parameter, both symmetric and asymmetric photon subtractions can further improve the quantum Cramér–Rao bound (i.e., the ultimate phase sensitivity), especially for single-mode photon subtraction. On the other hand, the quantum Cramér–Rao bound can be reached by parity detection for symmetric photon-subtracted two-mode squeezed vacuum states at particular values of the phase shift, but it is not valid for asymmetric photon-subtracted two-mode squeezed vacuum states. In addition, compared with the two-mode squeezed vacuum state, the phase sensitivity via parity detection with asymmetric photon-subtracted two-mode squeezed vacuum states will be getting worse. Thus, parity detection may not always be the optimal detection scheme for nonclassical states of light when they are considered as the interferometer states.

Chinese Physics B•Aug 6, 2019•7 citations
The removal of photons from certain quantum light sources produces so-called photon-subtracted states with enhanced mean photon numbers and intricate quantum correlations. Here, we propose an integrated photon-subtraction scheme that, contrary to previous approaches, is not heralded by photon correlation (coincidence) measurements. In this way, our technique exploits the “Welcher Weg” (“which way”) information problem, as it does not provide information about the modes from which the subtracted photons emanated. We show that this lack of information allows the generation of multiphoton states endowed with rich quantum correlations that strongly depend on the parity, evenness or oddness, of the number of subtracted photons.
Photon-subtracted two-mode squeezed vacuum states, a significant quantum resource, exhibit intricate correlations and unique quantum properties. In this work, we propose a theoretical yet experimentally feasible model to engineer these states using a waveguide trimer. Our study uncovers distinct characteristics of the photon-subtracted state depending on whether an even or odd number of photons is extracted, shedding light on the subtle relationship between quantum state manipulation and the parity of the number of subtracted photons. Furthermore, our integrated device facilitates the generation of multiphoton states with tunable correlations, offering significant potential for applications in quantum-enhanced technologies.
Abstract The quantum theory of electromagnetic radiation predicts characteristic statistical fluctuations for light sources as diverse as sunlight, laser radiation, and molecule fluorescence. Indeed, these underlying statistical fluctuations of light are associated with the fundamental physical processes behind their generation. In this contribution, we experimentally demonstrate that the manipulation of the quantum electromagnetic fluctuations of two-mode squeezed vacuum states leads to a family of quantum-correlated multiphoton states with tunable mean photon numbers and degree of correlation. Our technique relies on the use of conditional measurements to engineer the excitation mode of the field through the simultaneous subtraction of photons from two-mode squeezed vacuum states. The experimental generation of nonclassical multiphoton states by means of photon subtraction unveils novel mechanisms to control fundamental properties of light. As a remarkable example, we demonstrate the engineering of a quantum state of light with up to ten photons, exhibiting nearly Poissonian photon statistics, that constitutes an important step towards the generation of entangled lasers. Our technique enables a robust protocol to prepare quantum states with multiple photons in high-dimensional spaces and, as such, it constitutes a novel platform for exploring quantum phenomena in mesoscopic systems.
We study the application of photon-subtracted two-mode squeezed vacuum states (TMSVS), where identical photon numbers are subtracted from each beam, to the problem of quantum optical interferometry with the photon-number parity measurements scheme. Previously, Anisimov et al. [Phys. Rev. Lett.104, 103602 (2010)] have studied the prospect of using the TMSVS for parity measurements based interferometry. However, the joint photon number distribution of this state before beam splitting is thermal-like in each mode, meaning that its statistics are super-Poissonian and that the most probable state of the field is the double vacuum and that the average photon number is low. Furthermore, with these states the sensitivity of the phase-shift measurement is extremely sensitive to the size of the phase shift to be measured for large average photon numbers. The simultaneous subtraction of 1, 2, or 3 photons from each mode has the effects of increasing the average photon numbers of each mode and rendering the statistics nearly Poissonian and in some cases sub-Poissonian. We show that phase uncertainties for such states are less sensitive to the phase shift itself at large average photon numbers. We also show that the photon-subtracted TMSVS also lead to increased resolution.
Photon subtraction is useful to produce nonclassical states of light addressed to applications in photonic quantum technologies. After a very accelerated development, this technique makes possible obtaining either single photons or optical cats on demand. However, it lacks theoretical formulation enabling precise predictions for the produced fields. Based on the representation generated by the two-mode SU(2) coherent states, we introduce a model of entangled light beams leading to the subtraction of photons in one of the modes, conditioned to the detection of any photon in the other mode. We show that photon subtraction does not produce nonclassical fields from classical fields. It is also derived a compact expression for the output field from which the calculation of conditional probabilities is straightforward for any input state. Examples include the analysis of squeezed-vacuum and odd-squeezed states. We also show that injecting optical cats into a beam splitter gives rise to entangled states in the Bell representation.
Multiphoton subtraction from a traveling squeezed vacuum is a standard route to non-Gaussian optical-state engineering. High state-generation rates call for ultrashort optical pulses driven by high-repetition-rate lasers, but combining higher-order subtraction with ultrashort pulsed light and full state reconstruction remains challenging. Here we demonstrate up to four-photon subtraction from 10-ps squeezed-vacuum wave packets generated by a broadband waveguide optical parametric amplifier. Using a Ti-Au transition-edge sensor for photon-number-resolved heralding and homodyne tomography on the signal mode, we reconstruct the generated states up to the four-photon-subtracted case. The reconstructed states exhibit clear parity-dependent structure and visible Wigner-function negativity without loss correction. These results extend the experimentally accessible regime of multiphoton subtraction in broadband traveling optical modes and establish a platform for non-Gaussian optical resource-state engineering in continuous-variable quantum optics.
We investigate the sensitivity of phase estimation in a Mach–Zehnder interferometer with photon-subtracted two-mode squeezed vacuum states. Our results show that, for given initial squeezing parameter, both symmetric and asymmetric photon subtractions can further improve the quantum Cramér–Rao bound (i.e., the ultimate phase sensitivity), especially for single-mode photon subtraction. On the other hand, the quantum Cramér–Rao bound can be reached by parity detection for symmetric photon-subtracted two-mode squeezed vacuum states at particular values of the phase shift, but it is not valid for asymmetric photon-subtracted two-mode squeezed vacuum states. In addition, compared with the two-mode squeezed vacuum state, the phase sensitivity via parity detection with asymmetric photon-subtracted two-mode squeezed vacuum states will be getting worse. Thus, parity detection may not always be the optimal detection scheme for nonclassical states of light when they are considered as the interferometer states.