General method for extracting the quantum efficiency of dispersive qubit readout in circuit QED

We present and demonstrate a general three-step method for extracting the quantum efficiency of dispersive qubit readout in circuit QED. We use active depletion of post-measurement photons and optimal integration weight functions on two quadratures to maximize the signal-to-noise ratio of the non-steady-state homodyne measurement. We derive analytically and demonstrate experimentally that the method robustly extracts the quantum efficiency for arbitrary readout conditions in the linear regime. We use the proven method to optimally bias a Josephson traveling-wave parametric amplifier and to quantify different noise contributions in the readout amplification chain.Comment: 10 pages, 6 figure

Processing of semantic and grammatical gender in Spanish speakers with aphasia

Published online: 30 May 2021.Background: Previous studies have argued that there are two types of linguistic gender: grammatical gender, which is arbitrarily assigned to nouns, and semantic gender, which depends on the gender of the referent. Aim: We explore the hypothesis that these two types of gender entail distinct cognitive processes by investigating the performance of people with aphasia at the level of sentence processing. Methods and Procedure: Nine people with aphasia (seven with fluent aphasia) and a control group of thirteen age-matched healthy participants took part in a constrained completion choice task. The participants had to complete sentences in a way that made the last word gender congruent. The subjects of the sentences had either Semantic gender (enfermera, nurse; indicating the gender of the referent), Grammatical gender (silla, chair), or Opaque-Grammatical gender (tomate, tomato). Results: People with aphasia performed more poorly in all gender conditions than healthy controls. They also were less accurate in both the Grammatical and Opaque-Grammatical conditions than in the Semantic gender condition. Conclusion: We propose that because semantic gender provides more salient information, it is processed faster than grammatical gender.MC was supported by the postdoctoral Ramón y Cajal fellowship (RYC-2013-14013), Agencia Estatal de Investigación (AEI, National Research Agency), and Fondo Europeo de Desarrollo Regional (FEDER, European Regional Development Fund) under projects PSI2017-87784-R and RED2018- 102615-T

Deep-well ultrafast manipulation of a SQUID flux qubit

Superconducting devices based on the Josephson effect are effectively used for the implementation of qubits and quantum gates. The manipulation of superconducting qubits is generally performed by using microwave pulses with frequencies from 5 to 15 GHz, obtaining a typical operating clock from 100MHz to 1GHz. A manipulation based on simple pulses in the absence of microwaves is also possible. In our system a magnetic flux pulse modifies the potential of a double SQUID qubit from a symmetric double well to a single deep well condition. By using this scheme with a Nb/AlOx/Nb system we obtained coherent oscillations with sub-nanosecond period (tunable from 50ps to 200ps), very fast with respect to other manipulating procedures, and with a coherence time up to 10ns, of the order of what obtained with similar devices and technologies but using microwave manipulation. We introduce the ultrafast manipulation presenting experimental results, new issues related to this approach (such as the use of a feedback procedure for cancelling the effect of "slow" fluctuations), and open perspectives, such as the possible use of RSFQ logic for the qubit control.Comment: 9 pages, 7 figure

Old Italian Scrambling: the low left periphery of the clause

In this work I intend to investigate a basic notion which has been neglected since the minimalist perspective has been adopted, namely the GB notion of parameter as a unique abstract property ruling a number of different, apparently unrelated phenomena. If, as is generally accepted, language variation is a consequence of formal properties of functional heads, the notion of parameter in traditional terms has virtually no status in the theory of grammar, crosslinguistic differences being fragmented in a series of microparameters, each explaining only one phenomenon. However, the minimalist theory does provide us with alternative tools to capture “clusters” of phenomena. The aim of this work is to show on the basis of diachronic evidence that several phenomena indeed go together and can be traced back to a unique property involving the functional projection(s) located at the edge of phases. The empirical domain of investigation is the syntax of the low IP area and its relations to the syntax of the CP and the DP in Old Italian (OI). As diachronic change has the interesting peculiarity of revealing hidden connections among distinct phenomena, showing that they are lost or acquired at the same time; a number of apparently unrelated properties in OI can in fact be derived as different instances of one and the same abstract syntactic property encoded on a single functional head. While it is well known that Old Romance has the V2 property of subject inversion but not the linear V2 restriction, as V1, V3 and V* constructions with multiple Topics in front of a Focalized constituent are attested (see, a. o., Benincà (1985) (2004)), it has gone relatively unnoticed in the literature that OI permits (multiple) scrambling of objects and adverbial XPs to the left of the past participle yielding V-final clauses, as shown in (1): (1) a. quello che per uso è già dagli antichi servato, (Bono Giamboni, Vegezio, p. 108, r. 25-26) what that for use is already by the ancients preserved b. ed ha'mi la cosa molte volte ridetta (Bono Giamboni, Trattato, p. 131, rr. 20-21) and has-me the thing many times told OI scrambling targets both (non contrastive) focalized (1a) elements and there can be more than one element located to the left of the past participle (1b) (see Grewendorf (2004) for an analysis of scrambling in German as movement to Focus and Topic positions). In OI past participle agreement with postverbal objects (cf. (2)) was still possible: (2) c’ha rifiutata la nobile città di Giadres (Novellino, p. 133, r. 3) that has refused+agr the noble city of Giadres Scrambling is also found inside the DP: an adjective, part of an AdjP (3a), or a complement (3b) can be moved to a prenominal position: (3) a di gentile aspetto molto (Dante, Vita nuova, c. 1292-93) of gentle figure much b Sì come quando ordino di ritrarre dell’antiche scritte le cose che.. (Brun. Latini Rett. P 11 r.18) So as when (I) order to draw of the ancient writings the things that Interestingly, the noun heading the DP can also be fronted to the left of a quantifier (4a,b) to a higher position anche can be analyzed in the spirit of Longobardi’s work on construct state in Romance. (4) a donò anella molte (Novellino, p. 123 r. 51) gave rings many All these phenomena are lost at the same time, and precisely when the V2 property of subject inversion is lost: this suggests that they are all instances of the same abstract property. I propose that the simultaneous loss of V2, IP-scrambling, past participial agreement, DP-scrambling and N-fronting can be accounted for by assuming Belletti’s (2004) proposal that the left periphery of the high phase (CP) and the left periphery of the lower vP phase are construed in the same way, namely with a (set of ) TopicP followed by a FocusP and that this proposal can also be extended to the DP phase

Parallel Phases: a study on the high and low left periphery of Old Italian

In this work I will investigate a set of OV constructions in Old Italian (OI), a phenomenon which has been up to now neglected in the literature on Old Romance languages. Some cases of OV structures can be analyzed as V2 cases, with the Object in (some) SpecC position and the inflected verb in the corresponding C° head. There are however further cases which require a different treatment as the verbal form involved is a past participle, not an inflected verb.I intend to put forth an analysis in terms of movement of the XP to a low Focus (or Topic) position located to the left of the low vP phase, similar to (at least one type of) scrambling studied in the Germanic languages