### 6174 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: Tim Byrnes

Date: 2012-03-24

**qubit** gate operations that can be performed at a time reduced by a factor...**qubits** made of two component Bose-Einstein condensates (BECs) is analyzed...**qubit**. We illustrate the scheme by an application to Deutsch-s and Grover-s ... Quantum computation using **qubits** made of two component Bose-Einstein condensates (BECs) is analyzed. We construct a general framework for quantum algorithms to be executed using the collective states of the BECs. The use of BECs allows for an increase of energy scales via bosonic enhancement, resulting in two **qubit** gate operations that can be performed at a time reduced by a factor of N, where N is the number of bosons per **qubit**. We illustrate the scheme by an application to Deutsch-s and Grover-s algorithms, and discuss possible experimental implementations. Decoherence effects are analyzed under both general conditions and for the experimental implementation proposed.

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Contributors: Goldner, Philippe

Date: 2018-12-02

**Qubits**
in Rare Earth Doped Nanoparticles ... This presentation was given as an invited seminar at the Department of Applied Physics and Materials Science, Caltech, USA, on May 2, 2018, during a visit to the group of Prof. Andrei Faraon. It gives an overview of the current developments on rare earth based nanoscale systems for quantum technologies, focusing on results obtained within the NanOQTech project.

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Contributors: Duddell, William

Date: 1908-10-31

... n/a

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Contributors: Zou, Xudong, Seshia, Ashwin Arunkumar

Date: 2015-04-28

**frequency** stability of non-linear MEMS **oscillators** has not been previously...**frequency** stability of a nonlinear MEMS **oscillator** under variable damping...**oscillator** noise predict an improvement in **frequency** stability with increasing...**Oscillators**...**oscillator**. The random walk **frequency** noise and flicker **frequency** noise...**frequency** but also the phase/**frequency** noise of a nonlinear MEMS square ... Linear models for **oscillator** noise predict an improvement in **frequency** stability with increasing Quality factor. Although it is well known that this result does not apply to non-linear **oscillators**, systematic experimental investigations of the impact of damping on **frequency** stability of non-linear MEMS **oscillators** has not been previously reported. This paper studies the **frequency** stability of a nonlinear MEMS **oscillator** under variable damping conditions. Analytical and experimental investigation of a MEMS square-wave **oscillator** embedding a double-ended tuning fork resonator driven into the non-linear regime is introduced. The experimental results indicate that for a pre-set drive level, the variation of air-damping changes the onset of nonlinear behaviour in the resonator, which not only impacts the output **frequency** but also the phase/**frequency** noise of a nonlinear MEMS square wave **oscillator**. The random walk **frequency** noise and flicker **frequency** noise levels are strongly correlated with the non-linear operating point of the resonator, whereas the white phase and white **frequency** noise levels are impacted both by the output power and by operative nonlinearities.

Contributors: Owen, Edmund Thomas, Barnes, Crispin H. W.

Date: 2013-09-04

**oscillator** is proposed. The robustness of this technique is demonstrated...**qubit** to the electron's momentum. In order to incorporate this e ffect...**qubits** is the spin of an electron. However, in semiconductors, the spin-orbit...**qubits** are initially in the same state, no entanglement is generated as...**qubit**-**qubit**
interaction. Therefore, for an arbitrary initial state, this...two-**qubit** states using a pair of interacting particles in a one-dimensional ... Quantum states can contain correlations which are stronger than is possible in classical systems. Quantum information technologies use these correlations, which are known as entanglement, as a resource for implementing novel protocols in a diverse range of fields such as cryptography, teleportation and computing. However, current methods for generating the required entangled states are not necessarily robust against perturbations in the proposed systems. In this thesis, techniques will be developed for robustly generating the entangled states needed for these exciting new technologies.
The thesis starts by presenting some basic concepts in quantum information proccessing. In Ch. 2, the numerical methods which will be used to generate solutions for the dynamic systems in this thesis are presented. It is argued that using a GPU-accelerated staggered leapfrog technique provides a very efficient method for propagating the wave function.
In Ch. 3, a new method for generating maximally entangled two-**qubit** states using a pair of interacting particles in a one-dimensional harmonic **oscillator** is proposed. The robustness of this technique is demonstrated both analytically and numerically for a variety of interaction potentials. When the two **qubits** are initially in the same state, no entanglement is generated as there is no direct **qubit**-**qubit**
interaction. Therefore, for an arbitrary initial state, this process implements a root-of-swap entangling quantum gate. Some possible physical implementations of this proposal for low-dimensional semiconductor
systems are suggested.
One of the most commonly used **qubits** is the spin of an electron. However, in semiconductors, the spin-orbit interaction can couple this **qubit** to the electron's momentum. In order to incorporate this e ffect
into our numerical simulations, a new discretisation of this interaction is presented in Ch. 4 which is signi ficantly more accurate than traditional methods. This technique is shown to be similar to the standard discretisation for magnetic fields.
In Ch. 5, a simple spin-precession model is presented to predict the eff ect of the spin-orbit interaction on the entangling scheme of Ch. 3. It is shown that the root-of-swap quantum gate can be restored by introducing an additional constraint on the system. The robustness of the gate to perturbations in this constraint is demonstrated by presenting numerical solutions using the methods of Ch. 4.

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: Martin Vreugdenhil, John G R Jefferys, Peter D Ward, Olaleke O Oke, Andor Magony, Himashi Anver, Premysl Jiruska

Date: 2010-01-01

high-**frequency** gamma **oscillations** (fast-gamma; peak **frequency** approximately...**oscillations** generated in the deep layers. Fast-gamma was spatially less...low-**frequency** gamma **oscillations** (slow-gamma; peak **frequency** approximately...high-**frequency** gamma **oscillations** remain unknown. In rat visual cortex...high-**frequency** gamma **oscillations**. ... Synchronization of neuronal activity in the visual cortex at low (30-70 Hz) and high gamma band frequencies (> 70 Hz) has been associated with distinct visual processes, but mechanisms underlying high-**frequency** gamma **oscillations** remain unknown. In rat visual cortex slices, kainate and carbachol induce high-**frequency** gamma **oscillations** (fast-gamma; peak **frequency** approximately 80 Hz at 37 degrees C) that can coexist with low-**frequency** gamma **oscillations** (slow-gamma; peak **frequency** approximately 50 Hz at 37 degrees C) in the same column. Current-source density analysis showed that fast-gamma was associated with rhythmic current sink-source sequences in layer III and slow-gamma with rhythmic current sink-source sequences in layer V. Fast-gamma and slow-gamma were not phase-locked. Slow-gamma power fluctuations were unrelated to fast-gamma power fluctuations, but were modulated by the phase of theta (3-8 Hz) **oscillations** generated in the deep layers. Fast-gamma was spatially less coherent than slow-gamma. Fast-gamma and slow-gamma were dependent on gamma-aminobutyric acid (GABA)(A) receptors, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors and gap-junctions, their frequencies were reduced by thiopental and were weakly dependent on cycle amplitude. Fast-gamma and slow-gamma power were differentially modulated by thiopental and adenosine A(1) receptor blockade, and their frequencies were differentially modulated by N-methyl-D-aspartate (NMDA) receptors, GluK1 subunit-containing receptors and persistent sodium currents. Our data indicate that fast-gamma and slow-gamma both depend on and are paced by recurrent inhibition, but have distinct pharmacological modulation profiles. The independent co-existence of fast-gamma and slow-gamma allows parallel processing of distinct aspects of vision and visual perception. The visual cortex slice provides a novel in vitro model to study cortical high-**frequency** gamma **oscillations**.

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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: Drausin Wulsin, Brian Litt, Allison Pearce, Justin A Blanco, Abba Krieger, William C Stacey

Date: 2013-01-01

**frequency** events. These changes in relative rate occurred in pre- and ...High-**frequency** (100-500 Hz) **oscillations** (HFOs) recorded from intracranial...**frequency** events has also been identified. We hypothesize that temporal...high-**frequency** **oscillations** (HFOs) in each time epoch for dispersion analysis ... High-**frequency** (100-500 Hz) **oscillations** (HFOs) recorded from intracranial electrodes are a potential biomarker for epileptogenic brain. HFOs are commonly categorized as ripples (100-250 Hz) or fast ripples (250-500 Hz), and a third class of mixed **frequency** events has also been identified. We hypothesize that temporal changes in HFOs may identify periods of increased the likelihood of seizure onset. HFOs (86,151) from five patients with neocortical epilepsy implanted with hybrid (micro + macro) intracranial electrodes were detected using a previously validated automated algorithm run over all channels of each patient's entire recording. HFOs were characterized by extracting quantitative morphologic features and divided into four time epochs (interictal, preictal, ictal, and postictal) and three HFO clusters (ripples, fast ripples, and mixed events). We used supervised classification and nonparametric statistical tests to explore quantitative changes in HFO features before, during, and after seizures. We also analyzed temporal changes in the rates and proportions of events from each HFO cluster during these periods. We observed patient-specific changes in HFO morphology linked to fluctuation in the relative rates of ripples, fast ripples, and mixed **frequency** events. These changes in relative rate occurred in pre- and postictal periods up to thirty min before and after seizures. We also found evidence that the distribution of HFOs during these different time periods varied greatly between individual patients. These results suggest that temporal analysis of HFO features has potential for designing custom seizure prediction algorithms and for exploring the relationship between HFOs and seizure generation.

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