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Harnessing techniques from analog signal processing, we establish a new path for large-scale quantum computation.

We describe and implement a family of entangling gates activated by radio-frequency flux modulation applied to a tunable transmon that is statically coupled to a neighboring transmon. The effect of this modulation is the resonant exchange of photons directly between levels of the two-transmon system, obviating the need for mediating qubits or resonator modes and allowing for the full utilization of all qubits in a scalable architecture. The resonance condition is selective in both the frequency and amplitude of modulation and thus alleviates frequency crowding. We demonstrate the use of three such resonances to produce entangling gates that enable universal quantum computation: one iSWAP gate and two distinct controlled Z gates. We report interleaved randomized benchmarking results indicating gate error rates of 6% for the iSWAP (duration 135ns) and 9% for the controlled Z gates (durations 175 ns and 270 ns), limited largely by qubit coherence.A central challenge in building a scalable quantum computer with superconducting qubits is the execution of high-fidelity, two-qubit gates within an architecture containing many resonant elements. As more elements are added, or as the multiplicity of couplings between elements is increased, the frequency space of the design becomes crowded and device performance suffers. In architectures composed of transmon qubits [1], there are two main approaches to implementing two-qubit gates. The first utilizes fixed-frequency qubits with static couplings where the two-qubit operations are activated by applying transverse microwave drives [2][3][4][5][6][7][8]. While fixedfrequency qubits generally have long coherence times, this architecture requires satisfying stringent constraints on qubit frequencies and anharmonicities [5,6,8] which requires some tunability to scale to many qubits [9]. The second approach relies on frequency-tunable transmons, and two-qubit gates are activated by tuning qubits into and out of resonance with a particular transition [10][11][12][13][14][15][16]. However, tunability comes at the cost of additional decoherence channels, thus significantly limiting coherence times [17]. In this approach the delivery of shaped unbalanced control signals poses a challenge [15]. Such gates are furthermore sensitive to frequency crowdingavoiding unwanted crossings with neighboring qubit energy levels during gate operations limits the flexibility and connectivity of the architecture.An alternative to these approaches is to modulate a circuit's couplings or energy levels at a frequency corresponding to the detuning between particular energy levels of interest [18][19][20][21][22][23][24][25][26]. This enables an entangling gate between a qubit and a single resonator [21,22], a qubit and many resonator modes [26], two transmon qubits coupled by a tunable mediating qubit [16,25], or two tunable transmons coupled to a mediating resonator [23,24].Building on these earlier results, we implement two entangling gates, iSWAP and controlled Z (CZ), between a flux-tunable transmon an...

While the PGSI is indeed an established index of problem-gambling symptoms, it nevertheless does not quantify the degree of harm experienced by individuals at different points on the spectrum of gambling problems. The purpose of the present study was to establish the relationship between the PGSI category and health-related quality of life (HRQoL) decrements using a population health (PH) method. Harms reported by gamblers and affected others across the PGSI spectrums were transformed into 798 vignettes. A general population panel (N=786) and experts who work with gamblers (N=51) rated the impact of these vignette descriptions on quality of life using the Time Trade-Off task, and a Visual Analogue Scale incorporating 27 comparison conditions. Disability weights (DW) were then estimated for different levels of gambling symptoms. A DW of 0.44 was estimated for problem gamblers (PG), suggesting a reduction in the effective enjoyment of life by over 4 years for every 10 years in lifespan. Lower—but non-negligible—DWs of .14 and .29 were determined for low- and moderate-risk gamblers. Gambling is compared with a number of other conditions with respect to HRQoL impact. On average, PG harm appears to be similar to that of a manic episode of bipolar disorder and severe alcohol abuse disorder. We discuss advantages, and methodological challenges, in applying PH methods to measuring the severity of gambling problems in terms of HRQoL.Bien que l'indice du jeu excessif (PGSI) soit en effet un indice établi des symptômes liés aux problèmes de jeu, il ne quantifie pas le niveau de préjudice subi par les personnes situées à différents points sur le spectre des problèmes de jeu. Le but de l'étude a été d’établir la relation entre la catégorie PGSI et les écarts à la baisse en lien avec la qualité de vie liée à la santé (QVLS) en utilisant une méthode de santé de la population. Les torts signalés par les joueurs et les personnes touchées dans le spectre PGSI ont été transformés en 798 vignettes. Un groupe de population en général (N = 786) et des experts qui travaillent avec des joueurs compulsifs (N = 51) ont évalué l’incidence de ces descriptions de vignette sur la qualité de vie à l’aide de la tâche Time Trade-Off (marchandage de temps) et une échelle visuelle analogue intégrant 27 conditions de comparaison. Les poids d’incapacité (DW) ont ensuite été estimés pour différents niveaux de symptômes du jeu. Un DW de 0,44 a été estimé pour les joueurs compulsifs, ce qui laisse supposer une diminution de la jouissance réelle de la vie de plus de 4 ans pour chaque tranche de vie de 10 ans. Les DW inférieurs, mais non négligeables, de 0,14 et 0,29 ont été déterminés pour les joueurs à risque faible et modéré. Le jeu est comparé à un certain nombre d’autres conditions en ce qui concerne l’incidence de la qualité de vie liée à la santé (QVLS). En moyenne, le préjudice causé par un joueur compulsif s'apparente à celui d’un épisode maniaque de trouble bipolaire et d’un trouble sévère d’abus d’alcool. Nous discutons des avantages et des défis méthodologiques, en appliquant des méthodes de santé de la population pour mesurer la gravité des problèmes de jeu en termes de QVLS.

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