54 research outputs found

    Long-lived Microwave Electromechanical Systems Enabled by Cubic Silicon-Carbide Membrane Crystals

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    Cubic silicon-carbide crystals, known for their high thermal conductivity and in-plane stress, hold significant promise for the development of high-quality (QQ) mechanical oscillators. Enabling coherent electrical manipulation of long-lived mechanical resonators would be instrumental in advancing the development of phononic memories, repeaters, and transducers for microwave quantum states. In this study, we demonstrate the compatibility of high-stress and crystalline (3C-phase) silicon-carbide membranes with superconducting microwave circuits. We establish a coherent electromechanical interface for long-lived phonons, allowing precise control over the electromechanical cooperativity. This interface enables tunable slow-light time with group delays extending up to an impressive duration of \emph{an hour}. We then investigate a phononic memory based on the high-QQ (10810^{8}) silicon-carbide membrane, capable of storing and retrieving microwave coherent states \emph{on-demand}. The thermal and coherent components can be distinguished through state tomography in quadrature phase space, which shows an exponential increase and decay trend respectively as the storage time increases. The electromechanical interface and phononic memory made from crystalline silicon-carbide membrane possess enticing attributes, including low microwave-induced mechanical heating, phase coherence, an energy decay time of T1=19.9T_{1}=19.9~s, and it acquires less than one quantum noise within τcoh=41.3\tau_{\textrm{coh}}=41.3~ms storage period. These findings underscore the unique opportunities provided by cubic silicon-carbide membrane crystals for the storage and transfer of quantum information across distinct components of hybrid quantum systems

    Gate-Compatible Circuit QED in a Three-Dimensional Cavity Architecture

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    Semiconductor-based superconducting qubits offer a versatile platform for studying hybrid quantum devices in circuit quantum electrodynamics (cQED) architecture. Most of these cQED experiments utilize coplanar waveguides, where the incorporation of DC gate lines is straightforward. Here, we present a technique for probing gate-tunable hybrid devices using a three-dimensional (3D) microwave cavity. A recess is machined inside the cavity wall for the placement of devices and gate lines. We validate this design using a hybrid device based on an InAs-Al nanowire Josephson junction. The coupling between the device and the cavity is facilitated by a long superconducting strip, the antenna. The Josephson junction and the antenna together form a gatemon qubit. We further demonstrate the gate-tunable cavity shift and two-tone qubit spectroscopy. This technique could be used to probe various quantum devices and materials in a 3D cQED architecture that requires DC gate voltages

    The role of interleukin-12 in the pathogenesis of human systemic lupuserythematosus

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    Optomechanical Anti-Lasing with Infinite Group Delay at a Phase Singularity

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    Funding Information: This work is supported by the National Key Research and Development Program of China (Grant No. 2016YFA0301200), the National Natural Science Foundation of China (Grant No. 12004044, Grants No. 62074091 and No. U1930402), and Science Challenge Project (Grant No. TZ2018003), and by the Academy of Finland (Contracts No. 307757, No. 312057, No. 336810). Publisher Copyright: © 2021 American Physical Society.Singularities which symbolize abrupt changes and exhibit extraordinary behavior are of a broad interest. We experimentally study optomechanically induced singularities in a compound system consisting of a three-dimensional aluminum superconducting cavity and a metalized high-coherence silicon nitride membrane resonator. Mechanically induced coherent perfect absorption and anti-lasing occur simultaneously under a critical optomechanical coupling strength. Meanwhile, the phase around the cavity resonance undergoes an abrupt π-phase transition, which further flips the phase slope in the frequency dependence. The observed infinite discontinuity in the phase slope defines a singularity, at which the group velocity is dramatically changed. Around the singularity, an abrupt transition from an infinite group advance to delay is demonstrated by measuring a Gaussian-shaped waveform propagating. Our experiment may broaden the scope of realizing extremely long group delays by taking advantage of singularities.Peer reviewe

    Gene-Specific Epigenetic Regulation in Serious Infections with Systemic Inflammation

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    Inflammation is a fundamental biologic process that is evolutionally conserved by a germ line code. The interplay between epigenetics and environment directs the code into temporally distinct inflammatory responses, which can be acute or chronic. Here, we discuss the epigenetic processes of innate immune cells during serious infections with systemic inflammation in four stages: homeostasis, incitement, evolution, and resolution. We describe feed-forward loops of serious infections with systemic inflammation that create gene-specific silent facultative heterochromatin and active euchromatin according to gene function, and speculate on the role of epigenetics in survival

    Microrna-146a Regulates Both Transcription Silencing and Translation Disruption of TNF-α During TLR4-Induced Gene Reprogramming

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    Following the TLR-dependent initiation phase of acute systemic proinflammatory responses such as sepsis, an adaptive phase represses or activates a specific pattern of gene expression until the inflammation resolves. Here, we used the THP-1 sepsis cell model of bacterial LPS/endotoxin tolerance to show that TLR4- induced miR-146a supports the feed-forward adaptive processes that silence transcription and disrupt translation of acute proinflammatory genes. First, we found that miR-146a regulates a pathway that promotes the binding of transcription repressor RelB to the TNF-α promoter, a step known to precede histone and DNA modifications, which generate facultative heterochromatin to silence acute proinflammatory genes. However, once RelB binding occurred, miR-146a inhibition could not reverse compacted chromatin, and endotoxin tolerance persisted. Second, we observed that miR- 146a regulates a pathway that supports assembly of the translation repressor complex of TNF-α by preventing the interaction of the RNA-binding protein effector Ago2 and RBM4. We also determined that once endotoxin tolerance is established, and specific genes have been reprogrammed, transcription and translation disruption can be reversed only by simultaneously depleting RelB and inhibiting miR-146a. Thus, miR-146a induction supports the TLR4-dependent shift from initiation to gene-specific repression at two levels. Our results also imply that therapies designed to reverse endotoxin tolerance as potential therapies for sepsis should be directed at the transcription and translation pathways of reprogramming

    Parity-dependent unidirectional and chiral photon transfer in reversed-dissipation cavity optomechanics

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    Nonreciprocal elements, such as isolators and circulators, play an important role in classical and quantum information processing. Recently, strong nonreciprocal effects have been experimentally demonstrated in cavity optomechanical systems. In these approaches, the bandwidth of the nonreciprocal photon transmission is limited by the mechanical resonator linewidth, which is arguably much smaller than the linewidths of the cavity modes in most electromechanical or optomechanical devices. In this work, we demonstrate broadband nonreciprocal photon transmission in the reversed-dissipation regime, where the mechanical mode with a large decay rate can be adiabatically eliminated while mediating anti-PT-symmetric dissipative coupling with two kinds of phase factors. Adjusting the relative phases allows the observation of periodic Riemann-sheet structures with distributed exceptional points (Eps). At the Eps, destructive quantum interference breaks both the T- and P-inversion symmetry, resulting in unidirectional and chiral photon transmissions. In the reversed-dissipation regime, the nonreciprocal bandwidth is no longer limited by the mechanical mode linewidth but is improved to the linewidth of the cavity resonance. Furthermore, we find that the direction of the unidirectional and chiral energy transfer could be reversed by changing the parity of the Eps. Extending non-Hermitian couplings to a three-cavity model, the broken anti-PT-symmetry allows us to observe high-order Eps, at which a parity-dependent chiral circulator is demonstrated. The driving-phase controlled periodical Riemann sheets allow observation of the parity-dependent unidirectional and chiral energy transfer and thus provide a useful cell for building up nonreciprocal array and realizing topological, e.g., isolators, circulators, or amplifiers

    Phase-Controlled Pathway Interferences and Switchable Fast-Slow Light in a Cavity-Magnon Polariton System

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    Funding Information: This work is supported by the National Key R&D Program of China (Grant No. 2018YFA0306600), the CAS (Grants No. GJJSTD20170001 and No. QYZDY-SSW-SLH004), Anhui Initiative in Quantum Information Technologies (Grant No. AHY050000), and the Natural Science Foundation of China (NSFC) (Grant No. 12004044). F.N. is supported in part by: NTT Research, Army Research Office (ARO) (Grant No. W911NF-18-1-0358), Japan Science and Technology Agency (JST) (via the CREST Grant No. JPMJCR1676), Japan Society for the Promotion of Science (JSPS) (via the KAKENHI Grant No. and the JSPS-RFBR Grant No. JPJSBP120194828), the Asian Office of Aerospace Research and Development (AOARD), and the Foundational Questions Institute Fund (FQXi) via Grant No. FQXi-IAF19-06. Publisher Copyright: © 2021 American Physical Society. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.We study the phase-controlled transmission properties in a compound system consisting of a three-dimensional copper cavity and an yttrium-iron-garnet (YIG) sphere. By tuning the relative phase of the magnon pumping and cavity-probe tones, constructive and destructive interferences occur periodically, which strongly modify both the cavity-field transmission spectra and the group delay of light. Moreover, the tunable amplitude ratio between pump-probe tones allows us to further improve the signal absorption or amplification, accompanied by either significantly enhanced optical advance or delay. Both the phase and amplitude ratio can be used to realize in situ tunable and switchable fast-slow light. The tunable phase and amplitude ratio lead to the zero reflection of the transmitted light and an abrupt fast-slow light transition. Our results confirm that direct magnon pumping through the coupling loops provides a versatile route to achieve controllable signal transmission, storage, and communication, which can be further expanded to the quantum regime, realizing coherent-state processing or quantum-limited precise measurements.Peer reviewe
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