The Experts below are selected from a list of 189 Experts worldwide ranked by ideXlab platform
Fabio Pistolesi - One of the best experts on this subject based on the ideXlab platform.
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Charge fluctuations in single-Electron tunneling Oscillations
Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2012Co-Authors: Carlotta Negri, Fabio PistolesiAbstract:It has been predicted that in the presence of a sufficiently high-dissipative environment transport in a small tunnel junction can become extremely regular, giving rise to the phenomenon of single-Electron tunneling Oscillations. Recent progress in detection of high-frequency current fluctuations and the interest in single-Electron sources motivate further investigations on the expected accuracy of the charge Oscillations as a function of the impedance of the environment. In this paper we study theoretically the charge-fluctuation spectrum at finite frequency for the system at hand, and investigate its evolution as a function of the external impedance. The evolution and the disappearance of the single-Electron Oscillations peak is described by analytical and numerical methods.
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Charge fluctuations in single-Electron tunneling Oscillations
Physical Review B, 2012Co-Authors: Carlotta Negri, Fabio PistolesiAbstract:11 pages, 12 figuresInternational audienceIt has been predicted that in the presence of a sufficiently high-dissipative environment transport in a small tunnel junction can become extremely regular, giving rise to the phenomenon of single-Electron tunneling Oscillations. Recent progress in detection of high-frequency current fluctuations and the interest in single-Electron sources motivate further investigations on the expected accuracy of the charge Oscillations as a function of the impedance of the environment. In this paper we study theoretically the charge-fluctuation spectrum at finite frequency for the system at hand, and investigate its evolution as a function of the external impedance. The evolution and the disappearance of the single-Electron Oscillations peak is described by analytical and numerical methods
Carlotta Negri - One of the best experts on this subject based on the ideXlab platform.
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Charge fluctuations in single-Electron tunneling Oscillations
Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2012Co-Authors: Carlotta Negri, Fabio PistolesiAbstract:It has been predicted that in the presence of a sufficiently high-dissipative environment transport in a small tunnel junction can become extremely regular, giving rise to the phenomenon of single-Electron tunneling Oscillations. Recent progress in detection of high-frequency current fluctuations and the interest in single-Electron sources motivate further investigations on the expected accuracy of the charge Oscillations as a function of the impedance of the environment. In this paper we study theoretically the charge-fluctuation spectrum at finite frequency for the system at hand, and investigate its evolution as a function of the external impedance. The evolution and the disappearance of the single-Electron Oscillations peak is described by analytical and numerical methods.
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Charge fluctuations in single-Electron tunneling Oscillations
Physical Review B, 2012Co-Authors: Carlotta Negri, Fabio PistolesiAbstract:11 pages, 12 figuresInternational audienceIt has been predicted that in the presence of a sufficiently high-dissipative environment transport in a small tunnel junction can become extremely regular, giving rise to the phenomenon of single-Electron tunneling Oscillations. Recent progress in detection of high-frequency current fluctuations and the interest in single-Electron sources motivate further investigations on the expected accuracy of the charge Oscillations as a function of the impedance of the environment. In this paper we study theoretically the charge-fluctuation spectrum at finite frequency for the system at hand, and investigate its evolution as a function of the external impedance. The evolution and the disappearance of the single-Electron Oscillations peak is described by analytical and numerical methods
Jan Isberg - One of the best experts on this subject based on the ideXlab platform.
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observation of transferred Electron Oscillations in diamond
Applied Physics Letters, 2019Co-Authors: Nattakarn Suntornwipat, Saman Majdi, Markus Gabrysch, Ian Friel, Jan IsbergAbstract:The transferred-Electron oscillator (TEO), or Gunn oscillator, is a device used in microwave applications, which utilizes the negative differential mobility (NDM) effect to generate continuous Oscillations. Recently, NDM was observed in intrinsic single-crystalline chemical vapor deposition (SC-CVD) diamond. The occurrence was explained by the Electron repopulation between its different conduction band valleys. This paper presents the results of constructing a diamond TEO based on the NDM effect. A series of experiments have been performed for varying voltages, temperatures, and resonator parameters on three SC-CVD diamond samples of different thicknesses. For the temperature range of 90–300 K, we observe transferred-Electron Oscillations in diamond.The transferred-Electron oscillator (TEO), or Gunn oscillator, is a device used in microwave applications, which utilizes the negative differential mobility (NDM) effect to generate continuous Oscillations. Recently, NDM was observed in intrinsic single-crystalline chemical vapor deposition (SC-CVD) diamond. The occurrence was explained by the Electron repopulation between its different conduction band valleys. This paper presents the results of constructing a diamond TEO based on the NDM effect. A series of experiments have been performed for varying voltages, temperatures, and resonator parameters on three SC-CVD diamond samples of different thicknesses. For the temperature range of 90–300 K, we observe transferred-Electron Oscillations in diamond.
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Observation of transferred-Electron Oscillations in diamond
Applied Physics Letters, 2019Co-Authors: Nattakarn Suntornwipat, Saman Majdi, Markus Gabrysch, Ian Friel, Jan IsbergAbstract:The transferred-Electron oscillator (TEO) is a device used in microwave applications that utilizes the negative differential mobility (NDM) effect to generate continuous Oscillations. Recently, NDM was observed in intrinsic single-crystalline chemical vapor deposition (SC-CVD) diamond. The occurrence was explained by the Electron repopulation between its different conduction band valleys. This paper presents the results of constructing a diamond TEO based on the NDM effect. A series of experiments has been performed for varying voltages, temperatures and resonator parameters on three SC-CVD diamond samples of different thicknesses. For the temperature range 90-300 K, we observe transferred-Electron Oscillations in diamond.
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Investigation of transferred-Electron Oscillations in diamond
Applied Physics Letters, 2016Co-Authors: Nattakarn Suntornwipat, Saman Majdi, Markus Gabrysch, Jan IsbergAbstract:The recent discovery of Negative Differential Mobility (NDM) in intrinsic single-crystalline diamond enables the development of devices for high frequency applications. The Transferred-Electron Oscillator (TEO) is one example of such devices that uses the benefit of NDM to generate continuous Oscillations. This paper presents theoretical investigations of a diamond TEO in the temperature range of 110 to 140 K where NDM has been observed. Our simulations map out the parameter space in which transferred-Electron Oscillations are expected to occur for a specific device geometry. The results are promising and indicate that it is possible to fabricate diamond based TEO devices.
E Infeld - One of the best experts on this subject based on the ideXlab platform.
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Nonlinear Electron Oscillations in a viscous and resistive plasma.
Physical review. E Statistical nonlinear and soft matter physics, 2010Co-Authors: A A Skorupski, E InfeldAbstract:Nonlinear, spatially periodic, long-wavelength electrostatic modes of an Electron fluid oscillating against a motionless ion fluid (Langmuir waves) are given, with viscous and resistive effects included. The cold plasma approximation is adopted, which requires the wavelength to be sufficiently large. The pertinent requirement valid for large amplitude waves is determined. The general nonlinear solution of the continuity and momentum transfer equations for the Electron fluid along with Poisson's equation is obtained in simple parametric form. It is shown that in all typical hydrogen plasmas, the influence of plasma resistivity on the modes in question is negligible. Within the limitations of the solution found, the nonlinear time evolution of any (periodic) initial Electron number density profile ne(x,t=0) can be determined (examples). For the modes in question, an idealized model of a strictly cold and collisionless plasma is shown to be applicable to any real plasma, provided that the wavelength λ>>λmin(n(0),Te) , where n(0)=const and Te are the equilibrium values of the Electron number density and Electron temperature. Within this idealized model, the minimum of the initial Electron density n(e)(xmin,t=0) must be larger than half its equilibrium value, n(0)/2 . Otherwise, the corresponding maximum n(e)(xmax,t=τ(p)/2) , obtained after half a period of the plasma oscillation blows up. Relaxation of this restriction on n(e)(x,t=0) as one decreases λ , due to the increase of the Electron viscosity effects, is examined in detail. Strong plasma viscosity is shown to change considerably the density profile during the time evolution, e.g., by splitting the largest maximum in two.
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Nonlinear Electron Oscillations in a viscous and resistive plasma
Physical Review E, 2010Co-Authors: A A Skorupski, E InfeldAbstract:Nonlinear, spatially periodic, long-wavelength electrostatic modes of an Electron fluid oscillating against a motionless ion fluid (Langmuir waves) are given, with viscous and resistive effects included. The cold plasma approximation is adopted, which requires the wavelength to be sufficiently large. The pertinent requirement valid for large amplitude waves is determined. The general nonlinear solution of the continuity and momentum transfer equations for the Electron fluid along with Poisson's equation is obtained in simple parametric form. It is shown that in all typical hydrogen plasmas, the influence of plasma resistivity on the modes in question is negligible. Within the limitations of the solution found, the nonlinear time evolution of any (periodic) initial Electron number density profile ${n}_{e}(x,t=0)$ can be determined (examples). For the modes in question, an idealized model of a strictly cold and collisionless plasma is shown to be applicable to any real plasma, provided that the wavelength $\ensuremath{\lambda}⪢{\ensuremath{\lambda}}_{\text{min}}({n}_{0},{T}_{e})$, where ${n}_{0}=\text{const}$ and ${T}_{e}$ are the equilibrium values of the Electron number density and Electron temperature. Within this idealized model, the minimum of the initial Electron density ${n}_{e}({x}_{\text{min}},t=0)$ must be larger than half its equilibrium value, ${n}_{0}/2$. Otherwise, the corresponding maximum ${n}_{e}({x}_{\text{max}},t={\ensuremath{\tau}}_{p}/2)$, obtained after half a period of the plasma oscillation blows up. Relaxation of this restriction on ${n}_{e}(x,t=0)$ as one decreases $\ensuremath{\lambda}$, due to the increase of the Electron viscosity effects, is examined in detail. Strong plasma viscosity is shown to change considerably the density profile during the time evolution, e.g., by splitting the largest maximum in two.
Nikhil Chakrabarti - One of the best experts on this subject based on the ideXlab platform.
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Phase-mixing of large amplitude Electron Oscillations in a cold inhomogeneous plasma
Physics of Plasmas, 2018Co-Authors: Mithun Karmakar, Chandan Maity, Nikhil Chakrabarti, Sudip SenguptaAbstract:Phase-mixing of large amplitude non-relativistic Electron Oscillations around an inhomogeneous background of massive ions has been studied in a cold plasma. For our purpose, a space periodic but time independent ion density profile along with a perturbation in the Electron density is considered. An exact space-time dependent solution is presented in the parametric form by using Lagrangian coordinates. An inhomogeneity in the ion density causes the characteristic plasma frequency to acquire spatial dependency, leading to phase-mixing and thus breaking of excited Oscillations at arbitrary amplitudes. The effects of finite amplitude Electron density perturbation on the process of phase-mixing have also been discussed.
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Wave breaking of nonlinear Electron Oscillations in a warm magnetized plasma
Physics of Plasmas, 2014Co-Authors: Sourav Pramanik, Chandan Maity, Nikhil ChakrabartiAbstract:Wave breaking phenomena of nonlinear Electron Oscillations around a homogeneous background of massive ions have been studied in a warm magnetized plasma by using Lagrangian variables. An inhomogeneity in the background magnetic field is shown to induce phase mixing and thus breaking of the Oscillations. A nonlinear analysis in Lagrangian variables predicts that wave breaking may disappear above a critical value of the Electron temperature. An estimate for the critical temperature has been provided.
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Nonlinear Electron Oscillations in a warm plasma
Physics of Plasmas, 2013Co-Authors: Anwesa Sarkar, Chandan Maity, Nikhil ChakrabartiAbstract:A class of nonstationary solutions for the nonlinear Electron Oscillations of a warm plasma are presented using a Lagrangian fluid description. The solution illustrates the nonlinear steepening of an initial Gaussian Electron density disturbance and also shows collapse behavior in time. The obtained solution may indicate a class of nonlinear transient structures in an unmagnetized warm plasma.