### 5224 results for qubit oscillator frequency

Contributors: Eugene Grichuk, Margarita Kuzmina, Eduard Manykin

Date: 2010-09-26

**qubit** simulates the behavior of electric field of
polarized light beam...**qubit** model has been designed as a
stochastic **oscillator** formed by a pair...**qubits** that is
exploited as a computation resource in one-way quantum
...**oscillators** is
proposed for modeling of a cluster of entangled **qubits** ...**oscillators** with chaotically modulated limit cycle radii and
**frequencies**...one-**qubit**
gates are suggested. Changing of cluster entanglement degree...**qubit** cluster, is designed, and system of equations for
network dynamics...**oscillators**...**qubit** model has been designed as a
stochastic oscillator formed by a pair ... A network of coupled stochastic **oscillators** is
proposed for modeling of a cluster of entangled **qubits** that is
exploited as a computation resource in one-way quantum
computation schemes. A **qubit** model has been designed as a
stochastic **oscillator** formed by a pair of coupled limit cycle
**oscillators** with chaotically modulated limit cycle radii and
**frequencies**. The **qubit** simulates the behavior of electric field of
polarized light beam and adequately imitates the states of two-level
quantum system. A cluster of entangled **qubits** can be associated
with a beam of polarized light, light polarization degree being
directly related to cluster entanglement degree. Oscillatory network,
imitating **qubit** cluster, is designed, and system of equations for
network dynamics has been written. The constructions of one-**qubit**
gates are suggested. Changing of cluster entanglement degree caused
by measurements can be exactly calculated.

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Contributors: Weidinger, Daniel, Gruebele, Martin

Date: 2007-07-10

**Qubits** are encoded in 2n vibrational computing states on the ground electronic ... Accurate rotation-vibration energy levels and transition dipoles of the molecule thiophosgene are used to model the execution of quantum gates with shaped laser pulses. **Qubits** are encoded in 2n vibrational computing states on the ground electronic surface of the molecule. Computations are carried out by cycling amplitude between these computing states and a gateway state with a shaped laser pulse. The shaped pulse that performs the computation in the computing states is represented by a physical model of a 128-1024 channel pulse shaper. Pulse shapes are optimized with a standard genetic algorithm, yielding experimentally realizable computing pulses. We study the robustness of optimization as a function of the vibrational states selected, rotational level structure, additional vibrational levels not assigned to the computation, and compensation for laser power variation across a molecular ensemble.

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Contributors: Abdul-Niby, M., Alameen, M., Baitie, H.

Date: 2016-12-18

**frequency** synthesis, quadrature signal generation and phase locked loops...**oscillator** (ILO) of 35MHz **frequency**. Phase shifters at high **frequencies**...**oscillator**...**Oscillating** systems, locking of the **oscillators** can take place for injected...**frequency** to nth harmonics of the free-running **frequency**. In this paper ... In Self **Oscillating** systems, locking of the **oscillators** can take place for injected signals close in **frequency** to nth harmonics of the free-running **frequency**. In this paper, we present a simple design for digital phase shift control by using a harmonically injection locked **oscillator** (ILO) of 35MHz **frequency**. Phase shifters at high **frequencies** are essential in many communication system applications such as **frequency** synthesis, quadrature signal generation and phase locked loops (PLLs).

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Contributors: Georgiadis, Apostolos, Collado, Ana, Niotaki, Kyriaki

Date: 2015-05-01

**frequency** of the **oscillator**, while the output section is designed to maximize...**frequency** divide-by-3 circuit is presented based on an injection locked...**oscillator**. Substrate integrated waveguide (SIW) technology is used to...**oscillator**...**frequency** divider...**oscillator** circuit. A prototype is fabricated presenting a measured DC-RF...**frequency** with 3.7 dBm output power. An injection locking bandwidth of ... A 22.8 GHz analog **frequency** divide-by-3 circuit is presented based on an injection locked **oscillator**. Substrate integrated waveguide (SIW) technology is used to implement the input and output sections of the **frequency** divider circuit. The input SIW section at the gate of the active device permits the introduction of the injection signal at the third harmonic **frequency** of the **oscillator**, while the output section is designed to maximize the DC-RF conversion efficiency of the **oscillator** circuit. A prototype is fabricated presenting a measured DC-RF efficiency of 38.5% at 7.603 GHz output **frequency** with 3.7 dBm output power. An injection locking bandwidth of 301.4 MHz was obtained for a 1.5 dBm input injection signal at 22.8 GHz.

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Contributors: Lubich, L.

Date: 2018-02-20

**oscillator** outputs to the square waves obtained is calculated ignoring...**oscillator** phase noise spectrum. In this paper, accurate expressions are...**Oscillators** are often followed by square wave forming circuits and **frequency**...**oscillators**. The phase noise power spectral densities are calculated in...**oscillator**...**frequency** divider ... **Oscillators** are often followed by square wave forming circuits and **frequency** dividers. Traditionally, the level of the phase noise, transferred from the **oscillator** outputs to the square waves obtained is calculated ignoring the correlations in the **oscillator** phase noise spectrum. In this paper, accurate expressions are derived, taking into account the phase noise mechanisms in the **oscillators**. The phase noise power spectral densities are calculated in both the traditional way and by using the proposed expressions and they are compared. The situations where the proposed expressions can be useful are identified.

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Contributors: Meng Hu, Lili Wang

Date: 2012-08-26

**frequency** formulation...**oscillator** with fractional potential. By calculation and computer simulations...**oscillator**...**frequency** formulation is used to obtain a periodic solution for a nonlinear ... In this paper, He-s amplitude **frequency** formulation is used to obtain a periodic solution for a nonlinear **oscillator** with fractional potential. By calculation and computer simulations, compared with the exact solution shows that the result obtained is of high accuracy.

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Contributors: Liliia N. Butymova, Vladimir Ya Modorskii

Date: 2016-02-01

**oscillation** **frequency** from 50 to 150 Hz under P=10 MPa causes growth of...**oscillation** amplitude and **frequency**. The phase shift angle between gas-dynamic...**oscillations** and those of shaft displacement decreases from 3π/4 to π/...**oscillating** amplitude to decrease by 3 orders and **oscillation** **frequency**...**oscillation** phase shift...**Frequency** remains almost unchanged and the phase shift in the air changes ... To ensure the gas transmittal GCU's efficient operation, leakages through the labyrinth packings (LP) should be minimized. Leakages can be minimized by decreasing the LP gap, which in turn depends on thermal processes and possible rotor vibrations and is designed to ensure absence of mechanical contact. Vibration mitigation allows to minimize the LP gap. It is advantageous to research influence of processes in the dynamic gas-structure system on LP vibrations. This paper considers influence of rotor vibrations on LP gas dynamics and influence of the latter on the rotor structure within the FSI unidirectional dynamical coupled problem. Dependences of nonstationary parameters of gas-dynamic process in LP on rotor vibrations under various gas speeds and pressures, shaft rotation speeds and vibration amplitudes, and working medium features were studied. The programmed multi-processor ANSYS CFX was chosen as a numerical computation tool. The problem was solved using PNRPU high-capacity computer complex. Deformed shaft vibrations are replaced with an unyielding profile that moves in the fixed annulus "up-and-down" according to set harmonic rule. This solves a nonstationary gas-dynamic problem and determines time dependence of total gas-dynamic force value influencing the shaft. Pressure increase from 0.1 to 10 MPa causes growth of gas-dynamic force **oscillation** amplitude and **frequency**. The phase shift angle between gas-dynamic force **oscillations** and those of shaft displacement decreases from 3π/4 to π/2. Damping constant has maximum value under 1 MPa pressure in the gap. Increase of shaft **oscillation** **frequency** from 50 to 150 Hz under P=10 MPa causes growth of gas-dynamic force **oscillation** amplitude. Damping constant has maximum value at 50 Hz equaling 1.012. Increase of shaft vibration amplitude from 20 to 80 µm under P=10 MPa causes the rise of gas-dynamic force amplitude up to 20 times. Damping constant increases from 0.092 to 0.251. Calculations for various working substances (methane, perfect gas, air at 25 ˚С) prove the minimum gas-dynamic force persistent **oscillating** amplitude under P=0.1 MPa being observed in methane, and maximum in the air. **Frequency** remains almost unchanged and the phase shift in the air changes from 3π/4 to π/2. Calculations for various working substances (methane, perfect gas, air at 25 ˚С) prove the maximum gas-dynamic force **oscillating** amplitude under P=10 MPa being observed in methane, and minimum in the air. Air demonstrates surging. Increase of leakage speed from 0 to 20 m/s through LP under P=0.1 MPa causes the gas-dynamic force **oscillating** amplitude to decrease by 3 orders and **oscillation** **frequency** and the phase shift to increase 2 times and stabilize. Increase of leakage speed from 0 to 20 m/s in LP under P=1 MPa causes gas-dynamic force **oscillating** amplitude to decrease by almost 4 orders. The phase shift angle increases from π/72 to π/2. Oscillations become persistent. Flow rate proved to influence greatly on pressure **oscillations** amplitude and a phase shift angle. Work medium influence depends on operation conditions. At pressure growth, vibrations are mostly affected in methane (of working substances list considered), and at pressure decrease, in the air at 25 ˚С.

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Contributors: Wineland, David J.

Date: 2013-07-12

... n/a

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Contributors: Karlsson, J., Kunkel, N., Ikesue, A., Ferrier, A., Goldner, P.

Date: 2017-02-08

... We have measured inhomogeneous linewidths and coherence times (T2) of nuclear spin transitions in a Eu3+:Y2O3 transparent ceramic by an all-optical spin echo technique. The nuclear spin echo decay curves showed a strong modulation which was attributed to interaction with Y nuclei in the host. The coherence time of the 29 MHz spin transition in 151Eu3+ was 16 ms in a small applied magnetic field. Temperature dependent measurements showed that the coherence time was constant up to 18 K and was limited by spin-lattice relaxation for higher temperatures. Nuclear spin echoes in 153Eu3+ gave much weaker signals than for the case of 151Eu3+. The spin coherence time for the 73 MHz spin transition in 153Eu3+ was estimated to 14 ms in a small magnetic field. The study shows that the spin transitions of ceramic Eu3+:Y2O3 have coherence properties comparable to the best rare-earth-doped materials available. These results have been highlighted in JPhys+, news and views from the Journal of Physics series (IOP): https://jphysplus.iop.org/2017/02/09/long-spin-coherence-lifetime-in-eu3y2o3-ceramic/

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Contributors: de Cheveigné, Alain, Arzounian, Dorothée

Date: 2015-09-27

**Oscillations** are an important aspect of brain activity, but they often...**frequency** bands. Approach. Here, we propose a methodology that reveals...**oscillations**, leading to uncertainty as to the true oscillatory nature...**frequency** analysis kernels have a temporal extent that blurs the time ...**frequency** analysis methods with which it remains complementary.
... Objective. **Oscillations** are an important aspect of brain activity, but they often have a low signal- to-noise ratio (SNR) due to source-to-electrode mixing with competing brain activity and noise. Filtering can improve the SNR of narrowband signals, but it introduces ringing effects that may masquerade as genuine **oscillations**, leading to uncertainty as to the true oscillatory nature of the phenomena. Likewise, time–**frequency** analysis kernels have a temporal extent that blurs the time course of narrowband activity, introducing uncertainty as to timing and causal relations between events and/or **frequency** bands. Approach. Here, we propose a methodology that reveals narrowband activity within multichannel data such as electroencephalography, magnetoencephalography, electrocorticography or local field potential. The method exploits the between-channel correlation structure of the data to suppress competing sources by joint diagonalization of the covariance matrices of narrowband filtered and unfiltered data. Main results. Applied to synthetic and real data, the method effectively extracts narrowband components at unfavorable SNR. Significance. Oscillatory components of brain activity, including weak sources that are hard or impossible to observe using standard methods, can be detected and their time course plotted accurately. The method avoids the temporal artifacts of standard filtering and time–**frequency** analysis methods with which it remains complementary.

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