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Top: Rabi **oscillations** of the switching probability p (5×104 events) measured just after a resonant microwave pulse of duration τ. Solid line is a fit used to determine the Rabi **frequency**. Bottom: test of the linear dependence of the Rabi **frequency** with Uμw.
... (A) Calculated transition **frequency** ν01 as a function of φ and Ng. (B) Measured center transition **frequency** (symbols) as a function of reduced gate charge Ng for reduced flux φ=0 (right panel) and as a function of φ for Ng=0.5 (left panel), at 15mK. Spectroscopy is performed by measuring the switching probability p (105 events) when a continuous microwave irradiation of variable **frequency** is applied to the gate before readout. Continuous line: best fits used to determine circuit parameters. Inset: Narrowest line shape, obtained at the saddle point (Lorentzian fit with a FWHM Δν01=0.8MHz).

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The schematic figure for the projected quantum levels in IJJ composed of two junctions, the switching dynamics, and the transition between two quantum states caused by the irradiation of the microwave whose **frequency** is Ω2.
... Rabi-**oscillation**... The schematic figure for the quantum levels for IJJ, which are projected onto the potential barrier of the single Josephson junction without the coupling. The energy levels of the out-of-phase and the in-phase **oscillations** have the highest and the lowest eigen-energies, respectively.

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Typical convergence of an adaptive **frequency** **oscillator** (Eqs. (1)–(3)) driven by a harmonic signal (I(t)=sin(2πt)) and different coupling constants K. The coupling constant determines the convergence speed and the amplitude of **oscillations** around the **frequency** of the driving signal in steady state — the higher K the faster the convergence and the larger the **oscillations**.
... (a) Typical convergence of an adaptive **frequency** **oscillator** (Eqs. (1)–(3)) driven by a harmonic signal (I(t)=sin(2πt)). The **frequencies** converge in an oscillatory fashion towards the **frequency** of the input (indicated by the dashed line). After convergence it **oscillates** with a small amplitude around the **frequency** of the input. The coupling constant determines the convergence speed and the amplitude of **oscillations** around the **frequency** of the driving signal in steady state. In all figures, the top right panel shows the driving signals (note the different scales). (b)–(f) Non-harmonic driving signals. We depict representative results on the evolution of ωdωF=ω−ωFωF vs. time. The dashed line indicates the zero error between the intrinsic **frequency** ω and the base **frequency** ωF of the driving signals. (b) Square pulse I(t)=rect(ωFt), (c) Sawtooth I(t)=st(ωFt) (d) Chirp I(t)=cos(ωct) ωc=ωF(1+12(t1000)2). (Note that the graph of the input signal is illustrative only since the change in **frequency** takes much longer than illustrated.) (e) Signal with two non-commensurate **frequencies** I(t)=12[cos(ωFt)+cos(22ωFt)], i.e. a representative example how the system can evolve to different **frequency** components of the driving signal depending on the initial condition ωd(0)=ω(0)−ωF. (f) I(t) is the non-periodic output of the Rössler system. The Rössler signal has a 1/f broad-band spectrum, yet it has a clear maximum in the **frequency** spectrum. In order to assess the convergence we use ωF=2πfmax, where fmax is found numerically by FFT. The **oscillator** convergences to this **frequency**.
... (N=10000, K=0.1) — (a) The FFT (black line) of the Rössler signal (for t=[99800,100000]) in comparison with the distribution of the **frequencies** of the **oscillators** (grey bars, normalized to the number of **oscillators**) at time 105 s. The spectrum of the FFT has been discretized into the same bins as the statistics of the **oscillators** in order to allow for a good comparison with the results from the full-scale simulation. (b) Time-series of the output signal O(t) (bold line) vs the teaching signal T(t) (dashed line).
... Adaptive **frequency** **oscillator**... The structure of the dynamical system that is capable to reproduce a given teaching signal T(t). The system is made up of a pool of adaptive **frequency** **oscillators**. The mean field produced by the **oscillators** is fed back negatively on the **oscillators**. Due to the feedback structure and the adaptive **frequency** property of the **oscillators** it reconstructs the **frequency** spectrum of T(t) by the distribution of the intrinsic **frequencies**.
... Coupled **oscillators**... **Frequency** analysis... (a) (N=1000, K=200) — T(t) is a non-stationary input signal (cf. text), in contrast to Figs. 4 and 5 the histogram of the distribution of the **frequency** ωi is shown for every 5 s, the grey level corresponds to the number of **oscillators** in the bins (note the logarithmic scale). The thin white line indicates the theoretical instantaneous **frequency**. Thus, it can be seen that the distribution tracks very well the non-stationary spectrum, however about 4% of the **oscillators** diverge after the cross-over of the **frequencies**. (b) This plots outlines the maximum tracking performance of the system for non-stationary signal. The input signal has a sinusoidal varying **frequency**. The **frequency** response of the adaptation is plotted (see text for details). As comparison we plot the first-order transfer function HK∞ and the vertical line indicates ωs=1. (c) The grey area shows the region where the **frequency** response of the adaptation is H>22. While for slower non-stationary signals the upper bound is a function of K, the bound becomes independent of K for ωs>1 (red dashed line).

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Two-electron state amplitude in a dimer, with both molecules subject to a periodic force. After a full revolution the two electronic states each change their sign, leaving the total state invariant. **Frequencies**: ω1=1, ω2=1, G1=−100, G2=−200, G=40 (near adiabatic limit). Thick line: first, initially excited component. Medium thick line: second and third components. Thin line: fourth component.
... Two-electron state amplitudes in a dimer. The thick line shows the time dependent amplitude of the first (initially excited component), the thin line that of the second component in Eq. (5). **Frequencies**: ω1=1, ω2=4, G1=−40, G2=−80, G=16 (near adiabatic limit)
... Non-adiabaticity effects in the real part of the initially excited component, as a function of time. The **frequencies** on the two dimers are ω1=1 and ω2=2. The values of the coupling parameters are as follows. Thick line: G1=−80, G2=−160, G=40 (near adiabatic limit). Thin line: G1=−8, G2=−16, G=4 (non-adiabatic case)

Data Types:

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Nonlinear **oscillator**... Visibility dynamics in different timescales for initial state |Ψ2〉 and Γ=0. The timescale τp is associated to the decay of the envelope of the **oscillations** with characteristic time τr1. A very subtle increase in the amplitudes of the **oscillations** can be observed around t=τr2. The timescale of the fastest **oscillations** of the dynamics is τo.
... Visibility dynamics for initial state |Ψ2〉 and Γ varying from 0 to 0.1. For each value of Γ, the unit of time is chosen as the corresponding τp in (a), τr1 in (b), τr2 in (c), and τo in (d). For the majority of values of Γ investigated, the initial dynamics is flattened around t=2τp. Except for very small values of Γ, τr1 and τr2 are associated to partial revivals. When Γ increases, the number of fast initial **oscillations** decreases, but their characteristic durations are given by τo, which does not vary with Γ.
... Predictability dynamics in different timescales for initial state |Ψ2〉. The timescale τp is associated to the decay of the envelope of the **oscillations** with characteristic time τo. Revivals can be observed around the first multiples of τr.
... Predictability dynamics in different timescales for initial state |Ψ1〉. The timescale τp is associated to the rise and decay of the **oscillations** with characteristic time τo. Revivals occur in the region around τr and its first multiples.
... Visibility dynamics in different timescales for initial state |Ψ2〉 and Γ=0.1. The timescale τp is associated to the rise and decay of the initial dynamics. Both τr1 and τr2 are related to partial revivals. There are no **oscillations** besides the revivals and the initial rise and decay; the timescale of their duration is given by τo.

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Current-composed quantity Q(t) (solid lines) and the far-removed **qubit** QD occupancy, n3 (dashed lines), as a function of time for the horizontal **qubit**-detector connection, U13=U24=0, 2 or 4, respectively. μL=−μR=20, ΓL=5, ΓR=10, U12=U34=5 and the other parameters are the same as in Fig. 2. The lines for U13=U24=2 (4) are shifted by −1 (−2) for better visualisation.
... The sketch of the **qubit**-detector systems discussed in the text. Double quantum dot (1 and 4) between the left and right electron reservoirs stands for the **qubit** charge detector. **Qubit** is represented by two coupled quantum dots (2 and 3) occupied by a single electron. Straight black (zig-zag red) lines correspond to the tunnel matrix elements V14, V23 (Coulomb interactions, e.g. U14, U24) between the appropriate states. (For interpretation of the references to color in this figure caption, the reader is referred to the web version of this article.)
... The asymptotic pulse-induced current I(τ) against the time interval (pulse length) τ – for details see the text – and the charge occupation of the far-removed **qubit** QD, n3, (dashed lines) for the **qubit**-detector system schematically shown in Fig. 1b. The upper (bottom) panel corresponds to ΓL=5, ΓR=10 (ΓL=5, ΓR=1). μL=−μR=20 and the other parameters are the same as in Fig. 2. The current lines are multiplied by −2 for better visualisation.
... Current-composed quantity Q(t) (solid lines) and the charge occupation of the far-removed **qubit** QD, n3, (dashed lines) as a function of time for the **qubit**-detector system schematically shown in Fig. 1b. The upper (bottom) panel corresponds to (ΓL,ΓR)=(5,1) ((ΓL,ΓR)=(5,10)). The other parameters are: μL=−μR=2 or μL=−μR=20, ε1,2,3,4=0, U24=5, U14=50, n2(t<10)=0, n3(t<10)=1. The lines for μL=−μR=20 are shifted by −1 for better visualisation.
... Upper panel: Current-composed quantity Q(t) (solid lines) and the far-removed **qubit** QD occupancy, n3, (dashed lines) as a function of time for different **qubit**-detector connections shown in Fig. 1d (U12=5), Fig. 1c (U12=U24=5) and Fig. 1b (U24=5)—the upper, middle and lower curves, respectively. The bottom panel depicts the corresponding left (solid lines) and right (dashed lines) currents, IL(t), IR(t), flowing in the system for the above three **qubit**-wire connections. μL=−μR=2, ΓL=5, ΓR=10 and the other parameters are the same as in Fig. 2. The lines in the upper panel for U12=U24=5 and for U24=5 are shifted by −1 and −2, respectively, and by −0.15 and −0.3 in the bottom panel. Note different scales in the vertical axis of both panels.

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Average PTO power as a function of **oscillating** **frequency** for straight (♦: solid line) and bent leg (□: broken line) tines (**oscillation** angle β=+27°).
... Subsoiler draft signals with time for the control and the range of **oscillating** **frequencies**.
... Dominant **frequency** of draft signal over the **oscillating** **frequency** range.
... Proportion of cycle time for cutting and compaction phases versus **oscillating** **frequency** (**oscillation** angle β=+27°).
... Dominant **frequency** of torque signal over the **oscillating** **frequency** range.
... **Frequency**... **Oscillating** tine

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Equivalent circuit of the linearized **qubit**–SQUID system. ϕm and ϕp are the two independent variables of a DC SQUID. ϕm correpsonds to the circulating current of the SQUID, and ϕp couples with the ramping current of the SQUID. The capacitances of the inner **oscillator** loop and the external **oscillator** loop are Cm=2CJ and Cp, the shunt capacitance outside the SQUID. Flux of the three loops, q=q0σz, ϕm, and ϕp, are chosen as independent variables in the calculation. Each of the inductances in the three loops interacts by mutual inductances as are indicated by the paired dots near the inductances.
... The measuring circuit of the DC SQUID which surrounds the **qubit**. CJ and I0 are the capacitance and critical current of each of the junctions, and ϕi are the gauge-invariant phases of the junctions. The **qubit** is represented symbolically by a loop with an arrow indicating the magnetic moment of the |0〉 state. The SQUID is shunted by a capacitor Csh and the environmental impedance Z0(ω).

Data Types:

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