The Experts below are selected from a list of 31323 Experts worldwide ranked by ideXlab platform
Alexandre Blais - One of the best experts on this subject based on the ideXlab platform.
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circuit Quantum Electrodynamics
Reviews of Modern Physics, 2021Co-Authors: Alexandre Blais, S M Girvin, Arne L Grimsmo, Andreas WallraffAbstract:Quantum-mechanical effects at the macroscopic level were first explored in Josephson-junction-based superconducting circuits in the 1980s. In recent decades, the emergence of Quantum information science has intensified research toward using these circuits as qubits in Quantum information processors. The realization that superconducting qubits can be made to strongly and controllably interact with microwave photons, the quantized electromagnetic fields stored in superconducting circuits, led to the creation of the field of circuit Quantum Electrodynamics (QED), the topic of this review. While atomic cavity QED inspired many of the early developments of circuit QED, the latter has now become an independent and thriving field of research in its own right. Circuit QED allows the study and control of light-matter interaction at the Quantum level in unprecedented detail. It also plays an essential role in all current approaches to gate-based digital Quantum information processing with superconducting circuits. In addition, circuit QED provides a framework for the study of hybrid Quantum systems, such as Quantum dots, magnons, Rydberg atoms, surface acoustic waves, and mechanical systems interacting with microwave photons. Here the coherent coupling of superconducting qubits to microwave photons in high-quality oscillators focusing on the physics of the Jaynes-Cummings model, its dispersive limit, and the different regimes of light-matter interaction in this system are reviewed. Also discussed is coupling of superconducting circuits to their environment, which is necessary for coherent control and measurements in circuit QED, but which also invariably leads to decoherence. Dispersive qubit readout, a central ingredient in almost all circuit QED experiments, is also described. Following an introduction to these fundamental concepts that are at the heart of circuit QED, important use cases of these ideas in Quantum information processing and in Quantum optics are discussed. Circuit QED realizes a broad set of concepts that open up new possibilities for the study of Quantum physics at the macro scale with superconducting circuits and applications to Quantum information science in the widest sense.
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Quantum information processing and Quantum optics with circuit Quantum Electrodynamics
Nature Physics, 2020Co-Authors: Alexandre Blais, S M Girvin, William D OliverAbstract:Since the first observation of coherent Quantum behaviour in a superconducting qubit, now more than 20 years ago, there have been substantial developments in the field of superconducting Quantum circuits. One such advance is the introduction of the concepts of cavity Quantum Electrodynamics (QED) to superconducting circuits, to yield what is now known as circuit QED. This approach realizes in a single architecture the essential requirements for Quantum computation, and has already been used to run simple Quantum algorithms and to operate tens of superconducting qubits simultaneously. For these reasons, circuit QED is one of the leading architectures for Quantum computation. In parallel to these advances towards Quantum information processing, circuit QED offers new opportunities for the exploration of the rich physics of Quantum optics in novel parameter regimes in which strongly nonlinear effects are readily visible at the level of individual microwave photons. We review circuit QED in the context of Quantum information processing and Quantum optics, and discuss some of the challenges on the road towards scalable Quantum computation. The introduction of concepts from cavity Quantum Electrodynamics to superconducting circuits yielded circuit Quantum Electrodynamics, a platform eminently suitable to Quantum information processing and for the exploration of novel regimes in Quantum optics.
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Quantum zeno effect in the strong measurement regime of circuit Quantum Electrodynamics
New Journal of Physics, 2016Co-Authors: D H Slichter, Alexandre Blais, Clemens Muller, R Vijay, S J Weber, Irfan SiddiqiAbstract:We observe the Quantum Zeno effect—where the act of measurement slows the rate of Quantum state transitions—in a superconducting qubit using linear circuit Quantum Electrodynamics readout and a near-Quantum-limited following amplifier. Under simultaneous strong measurement and qubit drive, the qubit undergoes a series of Quantum jumps between states. These jumps are visible in the experimental measurement record and are analyzed using maximum likelihood estimation to determine qubit transition rates. The observed rates agree with both analytical predictions and numerical simulations. The analysis methods are suitable for processing general noisy random telegraph signals.
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thermal excitation of multi photon dressed states in circuit Quantum Electrodynamics
Physica Scripta, 2009Co-Authors: J M Fink, Alexandre Blais, M Goppl, M Baur, R Bianchetti, Stefan Filipp, P J Leek, L Steffen, Andreas WallraffAbstract:The exceptionally strong coupling realizable between superconducting qubits and photons stored in an on-chip microwave resonator allows for the detailed study of matter–light interactions in the realm of circuit Quantum Electrodynamics (QED). Here we investigate the resonant interaction between a single transmon-type multilevel artificial atom and weak thermal and coherent fields. We explore up to three photon dressed states of the coupled system in a linear response heterodyne transmission measurement. The results are in good quantitative agreement with a generalized Jaynes–Cummings model. Our data indicate that the role of thermal fields in resonant cavity QED can be studied in detail using superconducting circuits.
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cavity Quantum Electrodynamics for superconducting electrical circuits an architecture for Quantum computation
Physical Review A, 2004Co-Authors: Alexandre Blais, Andreas Wallraff, S M Girvin, Renshou Huang, R J SchoelkopfAbstract:We propose a realizable architecture using one-dimensional transmission line resonators to reach the strongcoupling limit of cavity Quantum Electrodynamics in superconducting electrical circuits. The vacuum Rabi frequency for the coupling of cavity photons to quantized excitations of an adjacent electrical circuit (qubit) can easily exceed the damping rates of both the cavity and qubit. This architecture is attractive both as a macroscopic analog of atomic physics experiments and for Quantum computing and control, since it provides strong inhibition of spontaneous emission, potentially leading to greatly enhanced qubit lifetimes, allows high-fidelity Quantum nondemolition measurements of the state of multiple qubits, and has a natural mechanism for entanglement of qubits separated by centimeter distances. In addition it would allow production of microwave photon states of fundamental importance for Quantum communication.
Jelena Vuckovic - One of the best experts on this subject based on the ideXlab platform.
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photon blockade in weakly driven cavity Quantum Electrodynamics systems with many emitters
Physical Review Letters, 2019Co-Authors: Rahul Trivedi, Marina Radulaski, Kevin A Fischer, Shanhui Fan, Jelena VuckovicAbstract:We use the scattering matrix formalism to analyze photon blockade in coherently driven cavity Quantum Electrodynamics systems with a weak drive. By approximating the weak coherent drive by an input single- and two-photon Fock state, we reduce the computational complexity of the transmission and the two-photon correlation function from exponential to polynomial in the number of emitters. This enables us to easily analyze cavity-based systems containing ∼50 Quantum emitters with modest computational resources. Using this approach we study the coherence statistics of photon blockade while increasing the number of emitters for resonant and detuned multiemitter cavity Quantum Electrodynamics systems-we find that increasing the number of emitters worsens photon blockade in resonant systems, and improves it in detuned systems. We also analyze the impact of inhomogeneous broadening in the emitter frequencies on the photon blockade through this system.
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cavity Quantum Electrodynamics with a single Quantum dot coupled to a photonic molecule
Physical Review B, 2012Co-Authors: Arka Majumdar, Armand Rundquist, Michal Bajcsy, Jelena VuckovicAbstract:We demonstrate the effects of cavity Quantum Electrodynamics for a Quantum dot coupled to a photonic molecule, consisting of a pair of coupled photonic crystal cavities. We show anti-crossing between the Quantum dot and the two super-modes of the photonic molecule, signifying achievement of the strong coupling regime. From the anti-crossing data, we estimate the contributions of both mode-coupling and intrinsic detuning to the total detuning between the super-modes. Finally, we also show signatures of off-resonant cavity-cavity interaction in the photonic molecule.
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photonic crystal microcavities for cavity Quantum Electrodynamics with a single Quantum dot
Applied Physics Letters, 2003Co-Authors: Jelena Vuckovic, Yoshihisa YamamotoAbstract:We propose a planar photonic crystal microcavity design specially tailored for cavity Quantum Electrodynamics with a single Quantum dot emitter embedded in semiconductor. With quality factor up to 45 000, mode volume smaller than a cubic optical wavelength in material, and electric field maximum located in the high-refractive index region at the cavity center, this design can enable both strong coupling and lasing with a single Quantum dot exciton. The achievable range of the quality factor to mode volume ratios and the feasible fabrication of the proposed structure make it favorable to other semiconductor microcavities.
Oskar Painter - One of the best experts on this subject based on the ideXlab platform.
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superconducting metamaterials for waveguide Quantum Electrodynamics
Nature Communications, 2018Co-Authors: Mohammad Mirhosseini, Eunjong Kim, Mahmoud Kalaee, Alp Sipahigil, Andrew J. Keller, Vinicius S. Ferreira, Oskar PainterAbstract:Embedding tunable Quantum emitters in a photonic bandgap structure enables control of dissipative and dispersive interactions between emitters and their photonic bath. Operation in the transmission band, outside the gap, allows for studying waveguide Quantum Electrodynamics in the slow-light regime. Alternatively, tuning the emitter into the bandgap results in finite-range emitter–emitter interactions via bound photonic states. Here, we couple a transmon qubit to a superconducting metamaterial with a deep sub-wavelength lattice constant (λ/60). The metamaterial is formed by periodically loading a transmission line with compact, low-loss, low-disorder lumped-element microwave resonators. Tuning the qubit frequency in the vicinity of a band-edge with a group index of ng = 450, we observe an anomalous Lamb shift of −28 MHz accompanied by a 24-fold enhancement in the qubit lifetime. In addition, we demonstrate selective enhancement and inhibition of spontaneous emission of different transmon transitions, which provide simultaneous access to short-lived radiatively damped and long-lived metastable qubit states.
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Superconducting metamaterials for waveguide Quantum Electrodynamics
Nature Communications, 2018Co-Authors: Mohammad Mirhosseini, Eunjong Kim, Mahmoud Kalaee, Alp Sipahigil, Andrew J. Keller, Vinicius S. Ferreira, Oskar PainterAbstract:The embedding of tunable Quantum emitters in a photonic bandgap structure enables the control of dissipative and dispersive interactions between emitters and their photonic bath. Operation in the transmission band, outside the gap, allows for studying waveguide Quantum Electrodynamics in the slow-light regime. Alternatively, tuning the emitter into the bandgap results in finite range emitter-emitter interactions via bound photonic states. Here we couple a transmon qubit to a superconducting metamaterial with a deep sub-wavelength lattice constant ($\lambda/60$). The metamaterial is formed by periodically loading a transmission line with compact, low loss, low disorder lumped element microwave resonators. We probe the coherent and dissipative dynamics of the system by measuring the Lamb shift and the change in the lifetime of the transmon qubit. Tuning the qubit frequency in the vicinity of a band-edge with a group index of $n_g = 450$, we observe an anomalous Lamb shift of 10 MHz accompanied by a 24-fold enhancement in the qubit lifetime. In addition, we demonstrate selective enhancement and inhibition of spontaneous emission of different transmon transitions, which provide simultaneous access to long-lived metastable qubit states and states strongly coupled to propagating waveguide modes.
Andreas Wallraff - One of the best experts on this subject based on the ideXlab platform.
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circuit Quantum Electrodynamics
Reviews of Modern Physics, 2021Co-Authors: Alexandre Blais, S M Girvin, Arne L Grimsmo, Andreas WallraffAbstract:Quantum-mechanical effects at the macroscopic level were first explored in Josephson-junction-based superconducting circuits in the 1980s. In recent decades, the emergence of Quantum information science has intensified research toward using these circuits as qubits in Quantum information processors. The realization that superconducting qubits can be made to strongly and controllably interact with microwave photons, the quantized electromagnetic fields stored in superconducting circuits, led to the creation of the field of circuit Quantum Electrodynamics (QED), the topic of this review. While atomic cavity QED inspired many of the early developments of circuit QED, the latter has now become an independent and thriving field of research in its own right. Circuit QED allows the study and control of light-matter interaction at the Quantum level in unprecedented detail. It also plays an essential role in all current approaches to gate-based digital Quantum information processing with superconducting circuits. In addition, circuit QED provides a framework for the study of hybrid Quantum systems, such as Quantum dots, magnons, Rydberg atoms, surface acoustic waves, and mechanical systems interacting with microwave photons. Here the coherent coupling of superconducting qubits to microwave photons in high-quality oscillators focusing on the physics of the Jaynes-Cummings model, its dispersive limit, and the different regimes of light-matter interaction in this system are reviewed. Also discussed is coupling of superconducting circuits to their environment, which is necessary for coherent control and measurements in circuit QED, but which also invariably leads to decoherence. Dispersive qubit readout, a central ingredient in almost all circuit QED experiments, is also described. Following an introduction to these fundamental concepts that are at the heart of circuit QED, important use cases of these ideas in Quantum information processing and in Quantum optics are discussed. Circuit QED realizes a broad set of concepts that open up new possibilities for the study of Quantum physics at the macro scale with superconducting circuits and applications to Quantum information science in the widest sense.
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thermal excitation of multi photon dressed states in circuit Quantum Electrodynamics
Physica Scripta, 2009Co-Authors: J M Fink, Alexandre Blais, M Goppl, M Baur, R Bianchetti, Stefan Filipp, P J Leek, L Steffen, Andreas WallraffAbstract:The exceptionally strong coupling realizable between superconducting qubits and photons stored in an on-chip microwave resonator allows for the detailed study of matter–light interactions in the realm of circuit Quantum Electrodynamics (QED). Here we investigate the resonant interaction between a single transmon-type multilevel artificial atom and weak thermal and coherent fields. We explore up to three photon dressed states of the coupled system in a linear response heterodyne transmission measurement. The results are in good quantitative agreement with a generalized Jaynes–Cummings model. Our data indicate that the role of thermal fields in resonant cavity QED can be studied in detail using superconducting circuits.
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coplanar waveguide resonators for circuit Quantum Electrodynamics
Journal of Applied Physics, 2008Co-Authors: M Goppl, Andreas Fragner, M Baur, R Bianchetti, Stefan Filipp, J M Fink, P J Leek, G Puebla, L Steffen, Andreas WallraffAbstract:High quality on-chip microwave resonators have recently found prominent new applications in Quantum optics and Quantum information processing experiments with superconducting electronic circuits, a field now known as circuit Quantum Electrodynamics (QED). They are also used as single photon detectors and parametric amplifiers. Here we analyze the physical properties of coplanar waveguide resonators and their relation to the materials properties for use in circuit QED. We have designed and fabricated resonators with fundamental frequencies from 2 to 9 GHz and quality factors ranging from a few hundreds to a several hundred thousands controlled by appropriately designed input and output coupling capacitors. The microwave transmission spectra measured at temperatures of 20 mK are shown to be in good agreement with theoretical lumped element and distributed element transmission matrix models. In particular, the experimentally determined resonance frequencies, quality factors, and insertion losses are fully and consistently explained by the two models for all measured devices. The high level of control and flexibility in design renders these resonators ideal for storing and manipulating Quantum electromagnetic fields in integrated superconducting electronic circuits.
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cavity Quantum Electrodynamics for superconducting electrical circuits an architecture for Quantum computation
Physical Review A, 2004Co-Authors: Alexandre Blais, Andreas Wallraff, S M Girvin, Renshou Huang, R J SchoelkopfAbstract:We propose a realizable architecture using one-dimensional transmission line resonators to reach the strongcoupling limit of cavity Quantum Electrodynamics in superconducting electrical circuits. The vacuum Rabi frequency for the coupling of cavity photons to quantized excitations of an adjacent electrical circuit (qubit) can easily exceed the damping rates of both the cavity and qubit. This architecture is attractive both as a macroscopic analog of atomic physics experiments and for Quantum computing and control, since it provides strong inhibition of spontaneous emission, potentially leading to greatly enhanced qubit lifetimes, allows high-fidelity Quantum nondemolition measurements of the state of multiple qubits, and has a natural mechanism for entanglement of qubits separated by centimeter distances. In addition it would allow production of microwave photon states of fundamental importance for Quantum communication.
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Strong coupling of a single photon to a superconducting qubit using circuit Quantum Electrodynamics.
Nature, 2004Co-Authors: Andreas Wallraff, D. I. Schuster, Anne Blais, Luigi Frunzio, Steven M. Girvin, Jonathan Majer, Robert J. SchoelkopfAbstract:The interaction of matter and light is one of the fundamental processes occurring in nature, and its most elementary form is realized when a single atom interacts with a single photon. Reaching this regime has been a major focus of research in atomic physics and Quantum optics for several decades and has generated the field of cavity Quantum Electrodynamics. Here we perform an experiment in which a superconducting two-level system, playing the role of an artificial atom, is coupled to an on-chip cavity consisting of a superconducting transmission line resonator. We show that the strong coupling regime can be attained in a solid-state system, and we experimentally observe the coherent interaction of a superconducting two-level system with a single microwave photon. The concept of circuit Quantum Electrodynamics opens many new possibilities for studying the strong interaction of light and matter. This system can also be exploited for Quantum information processing and Quantum communication and may lead to new approaches for single photon generation and detection.
Lilian Childress - One of the best experts on this subject based on the ideXlab platform.
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cavity Quantum Electrodynamics with color centers in diamond
arXiv: Quantum Physics, 2021Co-Authors: Erika Janitz, Mihir K Bhaskar, Lilian ChildressAbstract:Coherent interfaces between optical photons and long-lived matter qubits form a key resource for a broad range of Quantum technologies. Cavity Quantum Electrodynamics (cQED) offers a route to achieve such an interface by enhancing interactions between cavity-confined photons and individual emitters. Over the last two decades, a promising new class of emitters based on defect centers in diamond have emerged, combining long spin coherence times with atom-like optical transitions. More recently, advances in optical resonator technologies have made it feasible to realize cQED in diamond. This article reviews progress towards coupling color centers in diamond to optical resonators, focusing on approaches compatible with Quantum networks. We consider the challenges for cQED with solid-state emitters and introduce the relevant properties of diamond defect centers before examining two qualitatively different resonator designs: micron-scale Fabry-Perot cavities and diamond nanophotonic cavities. For each approach, we examine the underlying theory and fabrication, discuss strengths and outstanding challenges, and highlight state-of-the-art experiments.
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cavity Quantum Electrodynamics with color centers in diamond
Optica, 2020Co-Authors: Erika Janitz, Mihir K Bhaskar, Lilian ChildressAbstract:Coherent interfaces between optical photons and long-lived matter qubits form a key resource for a broad range of Quantum technologies. Cavity Quantum Electrodynamics (cQED) offers a route to achieve such an interface by enhancing interactions between cavity-confined photons and individual emitters. Over the last two decades, a promising new class of emitters based on defect centers in diamond has emerged, combining long spin coherence times with atom-like optical transitions. More recently, advances in optical resonator technologies have made it feasible to realize cQED in diamond. This article reviews progress towards coupling color centers in diamond to optical resonators, focusing on approaches compatible with Quantum networks. We consider the challenges for cQED with solid-state emitters and introduce the relevant properties of diamond defect centers before examining two qualitatively different resonator designs: micrometer-scale Fabry–Perot cavities and diamond nanophotonic cavities. For each approach, we examine the underlying theory and fabrication, discuss strengths and outstanding challenges, and highlight state-of-the-art experiments.
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mesoscopic cavity Quantum Electrodynamics with Quantum dots
Physical Review A, 2004Co-Authors: Lilian Childress, Anders S Sorensen, M D LukinAbstract:We describe an electrodynamic mechanism for coherent, Quantum-mechanical coupling between spatially separated Quantum dots on a microchip. The technique is based on capacitive interactions between the electron charge and a superconducting transmission line resonator, and is closely related to atomic cavity Quantum Electrodynamics. We investigate several potential applications of this technique which have varying degrees of complexity. In particular, we demonstrate that this mechanism allows design and investigation of an on-chip double-dot microscopic maser. Moreover, the interaction may be extended to couple spatially separated electron-spin states while only virtually populating fast-decaying superpositions of charge states. This represents an effective, controllable long-range interaction, which may facilitate implementation of Quantum information processing with electron-spin qubits and potentially allow coupling to other Quantum systems such as atomic or superconducting qubits.
