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

Optics and Photonics News

On-Chip Quantum Frequency Combs

Christian Reimer, Michael Kues, Piotr Roztocki, Fabio Grazioso, T. Johnston, Roberto Morandotti, Benjamin Wetzel, Brent E. Little, S. T. Chu, David Moss, Yaron Bromberg, Lucia Caspani

Published Dec 1, 2016• 3 citations
Publisher

Abstract

Nonclassical light sources of single and entangled photons are the backbone of future quantum communications infrastructure, and the cornerstone for realizing optical quantum computers. To reach practical applications, however, the enormous technical complexity of today’s sources must be drastically reduced through the development of integrated devices. In recent work, we have presented an approach for generating multiple two-photon and multiphoton entangled quantum states within a single waveguide mode.

DOI
10.1364/opn.27.12.000046

Related papers

Integrated photonic quantum frequency combs and applications

Michael Kues

Today’s quantum technology relies on the realization of large-scale non-classical systems in practical formats to enable quantum-accelerated computing, secure communications and enhanced sensing. Optical on-chip quantum frequency combs, characterized by many equidistantly spaced frequency modes, allow the storage of large amounts of quantum information. The combination with control techniques, using accessible state-of-the-art telecommunications infrastructure, can constitute a powerful frequency-domain quantum circuit with new functionalities and represents an approach towards realizing practical large-scale controllable quantum systems. In this presentation, we will review approaches for the efficient realization of quantum frequency combs in on-chip waveguide structures and micro-resonators. We will show their applicability for the realization of quantum systems with considerably enhanced complexity, particularly generating and manipulating on-chip multi-photon and high-dimensional quantum states as well as discrete high-dimensional cluster states, laying at the basis of measurement based-quantum computing. Building on this, the realization of frequency-domain Hong-Ou-Mandel interference of independent photons, fundamental to quantum information processing, as well as an outlook on frequency-domain circuits will be discussed.

Nanoscale and Quantum Materials: From Synthesis and Laser Processing to Applications•Apr 1, 2022•0 citations

Optical quantum state generation with integrated frequency comb sources.

Christian Reimer

The exploitation of quantum mechanics has the potential to solve important challenges and \nintroduce novel technologies enabling, among others, powerful computation (which can solve \ncertain problems exponentially faster than classical computers), perfectly secure communications, \nas well as sensing and imaging with precision and resolutions not achievable by classical means. \nIn order to make use of the unique properties of quantum physics, experimental platforms \nthat provide access to, and allow the control of quantum states, need to be developed. In \nparticular, quantum systems composed of multiple parties are required, where each party is in a \ncoherent superposition of states, and where multiples of such parties are in a coherent \nsuperposition with each other (e.g. being entangled). Additionally, in order to make use of such \nentangled quantum systems, it is required that each individual party can be coherently controlled \nand measured. The usability and available quantum resources of the entangled system is related \nto its size, which is proportional to the number of entangled parties, as well as the dimensionality \nof the superposition each party is in. For this reason, there is a imminent demand to achieve, \ninvestigate, and improve the generation and control of large quantum systems, comprised of as \nmany entangled parties as possible, where each party is in an ideally high-dimensional \nsuperposition. \nMany quantum platforms are currently subject to extensive research, such as trapped ions, \nsuperconducting circuits, defect centers in solid-state crystals, mechanical oscillators, and optical \nquantum states (i.e. photons). While all platforms provide distinct advantages (as well as \nchallenges), optical photon states are of particular interest, because they can interact with other \nquantum systems, and can be transmitted over long distances while preserving their quantum \ncoherence without the need for extensive shielding. A large variety of sources for optical \nquantum states has been demonstrated, however most such implementations suffer from high \ncomplexity, ultimately limiting their scalability. Integrated photonics has recently become a \nleading platform for the compact, cost-efficient, and stable generation and processing of optical \nquantum states. However, to date, integrated quantum sources have only been able to generate \nphoton pairs, which operated on single channels, and single polarization modes. Furthermore, in \nthe few realizations of on-chip entanglement, they were limited to two entangled parties, where \neach party was in a two-dimensional superposition. These limitations of current integrated photon sources arise in large part from the concepts currently exploited to generate and control these \nstates. In particular, path-entangled sources are the most commonly used, but increasing the \nquantum state complexity requires a significant, and very challenging, increase in device \ncomplexity. There is therefore an urgent need to develop new concepts that can achieve the onchip \ngeneration of large and complex photon states without increasing source complexity, while \nstill enabling coherent quantum state control and detection. \nIn this work, we aim to address these limitations by making use of multiple frequency and \ntemporal modes within a single spatial waveguide mode (therefore readily compatible with \nstandard optical fibers) of an on-chip microring resonator. This approach is in contrast to more \ncommonly used techniques relying on path entanglement, which exploits multiple spatial modes \nand generates entanglement by means of complex waveguide structures. Working within a single \nspatial mode, we achieve the first demonstration of pure heralded single photons and entangled \nphoton pairs, which are emitted on multiple frequency modes from a single source. We then \ndemonstrate the first generation of multi-photon entangled quantum states on a photonic chip. \nFinally, by making use of the spectral multi-mode nature of optical frequency combs, we achieve \nthe generation of photon pairs in a coherent superposition of multiple frequency modes, \nrepresenting the first generation of high-dimensional entangled states on a photonic chip. \nOur work represents a significant step forward in the generation of complex quantum \nstates on a photonic chip and in a single spatial mode compatible with standard optical fibers. In \naddition, we demonstrated coherent quantum state control and manipulation for all generated \nstates by means of standard telecommunications components, which could in the future be also \nintegrated on single, monolithic chip. Our results indicate that the exploitation of integrated \noptical frequency comb sources for the generation of optical quantum states can provide a \nscalable and practical platform for quantum technologies.

•Jan 1, 2017•0 citations

On-chip quantum frequency combs for complex photon state generation (Conference Presentation)

Michael Kues, Stefania Sciara, Piotr Roztocki +13 more

A key challenge in today’s quantum science is the realization of large-scale complex non-classical systems to enable e.g. ultra-secure communications, quantum-enhanced measurements, and computations faster than classical approaches. Optical frequency combs represent a powerful approach towards this, since they provide a very high number of temporal and frequency modes which can result in large-scale quantum systems. Here, we discuss the recent progress on the realization of integrated quantum frequency combs and reveal how their use in combination with on-chip and fiber-optic telecommunications components can enable quantum state control with new functionalities, yielding unprecedented capability.

Laser Resonators, Microresonators, and Beam Control•Mar 9, 2020•0 citations

On-chip frequency combs and telecommunications signal processing meet quantum optics

Christian Reimer, Yanbing Young Zhang, Piotr Roztocki +13 more

Entangled optical quantum states are essential towards solving questions in fundamental physics and are at the heart of applications in quantum information science. For advancing the research and development of quantum technologies, practical access to the generation and manipulation of photon states carrying significant quantum resources is required. Recently, integrated photonics has become a leading platform for the compact and cost-efficient generation and processing of optical quantum states. Despite significant advances, most on-chip nonclassical light sources are still limited to basic bi-photon systems formed by two-dimensional states (i.e., qubits). An interesting approach bearing large potential is the use of the time or frequency domain to enabled the scalable onchip generation of complex states. In this manuscript, we review recent efforts in using on-chip optical frequency combs for quantum state generation and telecommunications components for their coherent control. In particular, the generation of bi- and multi-photon entangled qubit states has been demonstrated, based on a discrete time domain approach. Moreover, the on-chip generation of high-dimensional entangled states (quDits) has recently been realized, wherein the photons are created in a coherent superposition of multiple pure frequency modes. The time- and frequency-domain states formed with on-chip frequency comb sources were coherently manipulated via off-the-shelf telecommunications components. Our results suggest that microcavity-based entangled photon states and their coherent control using accessible telecommunication infrastructures can open up new venues for scalable quantum information science.

Frontiers of Optoelectronics•Jun 1, 2018•7 citations

Complex Quantum State Generation and Coherent Control Based on Integrated Frequency Combs

Piotr Roztocki, Stefania Sciara, Christian Reimer +13 more

The investigation of integrated frequency comb sources characterized by equidistant spectral modes was initially driven by considerations toward classical applications, seeking a more practical and miniaturized way to generate stable broadband sources of light. Recently, in the context of scaling the complexity of optical quantum circuits, these on-chip approaches have provided a new framework to address the challenges associated with non-classical state generation and manipulation. For example, multi-photon and high-dimensional states were to date either inaccessible, lacked scalability, or were difficult to manipulate, requiring elaborate approaches. The emerging field of quantum frequency combs studying spectral multimode sources based on the judicious excitation of (typically) third-order nonlinear optical micro-cavities has begun to address these issues. Several quantum sources based on this concept have already been demonstrated, among them are combs of correlated photons, cross-polarized photon pairs, entangled photon pairs, multi-photon states, and high-dimensional entangled states. While sources have achieved increasing complexity, so have coherent state processing operations, demonstrated in a practical manner using standard telecommunications components. Here, we review our recent work in the development of this framework, with a focus on multi-photon and high-dimensional states. The integrated frequency comb platform thus demonstrates significant potential for the development of meaningful quantum optical technologies.

Journal of Lightwave Technology•Nov 13, 2018•188 citations

On-chip quantum state generation by means of integrated frequency combs

Stefania Sciara, Michael Kues, Christian Reimer +8 more

Summary form only given. This paper investigates different approaches to generate optical quantum states by means of integrated optical frequency combs. These include the generation of multiplexed heralded single-photons, the first realization of cross-polarized photon-pairs on a photonic chip, the first generation of multiple two-photon entangled states, and the first realizations of multi-photon entangled quantum states on a photonic chip.

IEEE/LEOS Summer Topical Meetings•Jul 1, 2017•0 citations
Nonclassical light sources of single and entangled photons are the backbone of future quantum communications infrastructure, and the cornerstone for realizing optical quantum computers. To reach practical applications, however, the enormous technical complexity of today’s sources must be drastically reduced through the development of integrated devices. In recent work, we have presented an approach for generating multiple two-photon and multiphoton entangled quantum states within a single waveguide mode.
Today’s quantum technology relies on the realization of large-scale non-classical systems in practical formats to enable quantum-accelerated computing, secure communications and enhanced sensing. Optical on-chip quantum frequency combs, characterized by many equidistantly spaced frequency modes, allow the storage of large amounts of quantum information. The combination with control techniques, using accessible state-of-the-art telecommunications infrastructure, can constitute a powerful frequency-domain quantum circuit with new functionalities and represents an approach towards realizing practical large-scale controllable quantum systems. In this presentation, we will review approaches for the efficient realization of quantum frequency combs in on-chip waveguide structures and micro-resonators. We will show their applicability for the realization of quantum systems with considerably enhanced complexity, particularly generating and manipulating on-chip multi-photon and high-dimensional quantum states as well as discrete high-dimensional cluster states, laying at the basis of measurement based-quantum computing. Building on this, the realization of frequency-domain Hong-Ou-Mandel interference of independent photons, fundamental to quantum information processing, as well as an outlook on frequency-domain circuits will be discussed.
The exploitation of quantum mechanics has the potential to solve important challenges and \nintroduce novel technologies enabling, among others, powerful computation (which can solve \ncertain problems exponentially faster than classical computers), perfectly secure communications, \nas well as sensing and imaging with precision and resolutions not achievable by classical means. \nIn order to make use of the unique properties of quantum physics, experimental platforms \nthat provide access to, and allow the control of quantum states, need to be developed. In \nparticular, quantum systems composed of multiple parties are required, where each party is in a \ncoherent superposition of states, and where multiples of such parties are in a coherent \nsuperposition with each other (e.g. being entangled). Additionally, in order to make use of such \nentangled quantum systems, it is required that each individual party can be coherently controlled \nand measured. The usability and available quantum resources of the entangled system is related \nto its size, which is proportional to the number of entangled parties, as well as the dimensionality \nof the superposition each party is in. For this reason, there is a imminent demand to achieve, \ninvestigate, and improve the generation and control of large quantum systems, comprised of as \nmany entangled parties as possible, where each party is in an ideally high-dimensional \nsuperposition. \nMany quantum platforms are currently subject to extensive research, such as trapped ions, \nsuperconducting circuits, defect centers in solid-state crystals, mechanical oscillators, and optical \nquantum states (i.e. photons). While all platforms provide distinct advantages (as well as \nchallenges), optical photon states are of particular interest, because they can interact with other \nquantum systems, and can be transmitted over long distances while preserving their quantum \ncoherence without the need for extensive shielding. A large variety of sources for optical \nquantum states has been demonstrated, however most such implementations suffer from high \ncomplexity, ultimately limiting their scalability. Integrated photonics has recently become a \nleading platform for the compact, cost-efficient, and stable generation and processing of optical \nquantum states. However, to date, integrated quantum sources have only been able to generate \nphoton pairs, which operated on single channels, and single polarization modes. Furthermore, in \nthe few realizations of on-chip entanglement, they were limited to two entangled parties, where \neach party was in a two-dimensional superposition. These limitations of current integrated photon sources arise in large part from the concepts currently exploited to generate and control these \nstates. In particular, path-entangled sources are the most commonly used, but increasing the \nquantum state complexity requires a significant, and very challenging, increase in device \ncomplexity. There is therefore an urgent need to develop new concepts that can achieve the onchip \ngeneration of large and complex photon states without increasing source complexity, while \nstill enabling coherent quantum state control and detection. \nIn this work, we aim to address these limitations by making use of multiple frequency and \ntemporal modes within a single spatial waveguide mode (therefore readily compatible with \nstandard optical fibers) of an on-chip microring resonator. This approach is in contrast to more \ncommonly used techniques relying on path entanglement, which exploits multiple spatial modes \nand generates entanglement by means of complex waveguide structures. Working within a single \nspatial mode, we achieve the first demonstration of pure heralded single photons and entangled \nphoton pairs, which are emitted on multiple frequency modes from a single source. We then \ndemonstrate the first generation of multi-photon entangled quantum states on a photonic chip. \nFinally, by making use of the spectral multi-mode nature of optical frequency combs, we achieve \nthe generation of photon pairs in a coherent superposition of multiple frequency modes, \nrepresenting the first generation of high-dimensional entangled states on a photonic chip. \nOur work represents a significant step forward in the generation of complex quantum \nstates on a photonic chip and in a single spatial mode compatible with standard optical fibers. In \naddition, we demonstrated coherent quantum state control and manipulation for all generated \nstates by means of standard telecommunications components, which could in the future be also \nintegrated on single, monolithic chip. Our results indicate that the exploitation of integrated \noptical frequency comb sources for the generation of optical quantum states can provide a \nscalable and practical platform for quantum technologies.
A key challenge in today’s quantum science is the realization of large-scale complex non-classical systems to enable e.g. ultra-secure communications, quantum-enhanced measurements, and computations faster than classical approaches. Optical frequency combs represent a powerful approach towards this, since they provide a very high number of temporal and frequency modes which can result in large-scale quantum systems. Here, we discuss the recent progress on the realization of integrated quantum frequency combs and reveal how their use in combination with on-chip and fiber-optic telecommunications components can enable quantum state control with new functionalities, yielding unprecedented capability.
Entangled optical quantum states are essential towards solving questions in fundamental physics and are at the heart of applications in quantum information science. For advancing the research and development of quantum technologies, practical access to the generation and manipulation of photon states carrying significant quantum resources is required. Recently, integrated photonics has become a leading platform for the compact and cost-efficient generation and processing of optical quantum states. Despite significant advances, most on-chip nonclassical light sources are still limited to basic bi-photon systems formed by two-dimensional states (i.e., qubits). An interesting approach bearing large potential is the use of the time or frequency domain to enabled the scalable onchip generation of complex states. In this manuscript, we review recent efforts in using on-chip optical frequency combs for quantum state generation and telecommunications components for their coherent control. In particular, the generation of bi- and multi-photon entangled qubit states has been demonstrated, based on a discrete time domain approach. Moreover, the on-chip generation of high-dimensional entangled states (quDits) has recently been realized, wherein the photons are created in a coherent superposition of multiple pure frequency modes. The time- and frequency-domain states formed with on-chip frequency comb sources were coherently manipulated via off-the-shelf telecommunications components. Our results suggest that microcavity-based entangled photon states and their coherent control using accessible telecommunication infrastructures can open up new venues for scalable quantum information science.
The investigation of integrated frequency comb sources characterized by equidistant spectral modes was initially driven by considerations toward classical applications, seeking a more practical and miniaturized way to generate stable broadband sources of light. Recently, in the context of scaling the complexity of optical quantum circuits, these on-chip approaches have provided a new framework to address the challenges associated with non-classical state generation and manipulation. For example, multi-photon and high-dimensional states were to date either inaccessible, lacked scalability, or were difficult to manipulate, requiring elaborate approaches. The emerging field of quantum frequency combs studying spectral multimode sources based on the judicious excitation of (typically) third-order nonlinear optical micro-cavities has begun to address these issues. Several quantum sources based on this concept have already been demonstrated, among them are combs of correlated photons, cross-polarized photon pairs, entangled photon pairs, multi-photon states, and high-dimensional entangled states. While sources have achieved increasing complexity, so have coherent state processing operations, demonstrated in a practical manner using standard telecommunications components. Here, we review our recent work in the development of this framework, with a focus on multi-photon and high-dimensional states. The integrated frequency comb platform thus demonstrates significant potential for the development of meaningful quantum optical technologies.