• Title/Summary/Keyword: Gaussian potential

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The Influence of Confining Parameters on the Ground State Properties of Interacting Electrons in a Two-dimensional Quantum Dot with Gaussian Potential

  • Gulveren, Berna
    • Journal of the Korean Physical Society
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    • v.73 no.11
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    • pp.1612-1618
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    • 2018
  • In this work, the ground-state properties of an interacting electron gas confined in a two-dimensional quantum dot system with the Gaussian potential ${\upsilon}(r)=V_0(1-{\exp}(-r^2/p))$, where $V_0$ and p are confinement parameters, are determined numerically by using the Thomas-Fermi approximation. The shape of the potential is modified by changing the $V_0$ and the p values, and the influence of the confining potential on the system's properties, such as the chemical energy, the density profile, the kinetic energy, the confining energy, etc., is analyzed for both the non-interacting and the interacting cases. The results are compared with those calculated for a harmonic potential, and excellent agreement is obtained in the limit of high p values for both the non-interacting and the interacting cases.

The Analysis of Breakdown Voltage for the Double-gate MOSFET Using the Gaussian Doping Distribution

  • Jung, Hak-Kee
    • Journal of information and communication convergence engineering
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    • v.10 no.2
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    • pp.200-204
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    • 2012
  • This study has presented the analysis of breakdown voltage for a double-gate metal-oxide semiconductor field-effect transistor (MOSFET) based on the doping distribution of the Gaussian function. The double-gate MOSFET is a next generation transistor that shrinks the short channel effects of the nano-scaled CMOSFET. The degradation of breakdown voltage is a highly important short channel effect with threshold voltage roll-off and an increase in subthreshold swings. The analytical potential distribution derived from Poisson's equation and the Fulop's avalanche breakdown condition have been used to calculate the breakdown voltage of a double-gate MOSFET for the shape of the Gaussian doping distribution. This analytical potential model is in good agreement with the numerical model. Using this model, the breakdown voltage has been analyzed for channel length and doping concentration with parameters such as projected range and standard projected deviation of Gaussian function. As a result, since the breakdown voltage is greatly changed for the shape of the Gaussian function, the channel doping distribution of a double-gate MOSFET has to be carefully designed.

Application of Genetic Algorithm for Large-Scale Multiuser MIMO Detection with Non-Gaussian Noise

  • Ran, Rong
    • Journal of information and communication convergence engineering
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    • v.20 no.2
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    • pp.73-78
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    • 2022
  • Based on experimental measurements conducted on many different practical wireless communication systems, ambient noise has been shown to be decidedly non-Gaussian owing to impulsive phenomena. However, most multiuser detection techniques proposed thus far have considered Gaussian noise only. They may therefore suffer from a considerable performance loss in the presence of impulsive ambient noise. In this paper, we consider a large-scale multiuser multiple-input multiple-output system in the presence of non-Gaussian noise and propose a genetic algorithm (GA) based detector for large-dimensional multiuser signal detection. The proposed algorithm is more robust than linear multi-user detectors for non-Gaussian noise because it uses a multi-directional search to manipulate and maintain a population of potential solutions. Meanwhile, the proposed GA-based algorithm has a comparable complexity because it does not require any complicated computations (e.g., a matrix inverse or derivation). The simulation results show that the GA offers a performance gain over the linear minimum mean square error algorithm for both non-Gaussian and Gaussian noise.

Analysis of Subthreshold Current Deviation for Channel Doping of Double Gate MOSFET (이중게이트 MOSFET의 채널도핑에 다른 문턱전압이하 전류 변화 분석)

  • Jung, Hakkee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.6
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    • pp.1409-1413
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    • 2013
  • This paper analyzed the change of subthreshold current for channel doping concentration of double gate(DG) MOSFET. Poisson's equation had been used to analyze the potential distribution in channel, and Gaussian function had been used as carrier distribution. The potential distribution was obtained as the analytical function of channel dimension, using the boundary condition. The subthreshold current had been analyzed for channel doping concentration, and projected range and standard projected deviation of Gaussian function. Since this analytical potential model was verified in the previous papers, we used this model to analyze the subthreshold current. As a result, we know the subthreshold current was influenced on parameters of Gaussian function and channel doping concentration for DGMOSFET.

Solving Time-dependent Schrödinger Equation Using Gaussian Wave Packet Dynamics

  • Lee, Min-Ho;Byun, Chang Woo;Choi, Nark Nyul;Kim, Dae-Soung
    • Journal of the Korean Physical Society
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    • v.73 no.9
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    • pp.1269-1278
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    • 2018
  • Using the thawed Gaussian wave packets [E. J. Heller, J. Chem. Phys. 62, 1544 (1975)] and the adaptive reinitialization technique employing the frame operator [L. M. Andersson et al., J. Phys. A: Math. Gen. 35, 7787 (2002)], a trajectory-based Gaussian wave packet method is introduced that can be applied to scattering and time-dependent problems. This method does not require either the numerical multidimensional integrals for potential operators or the inversion of nearly-singular matrices representing the overlap of overcomplete Gaussian basis functions. We demonstrate a possibility that the method can be a promising candidate for the time-dependent $Schr{\ddot{o}}dinger$ equation solver by applying to tunneling, high-order harmonic generation, and above-threshold ionization problems in one-dimensional model systems. Although the efficiency of the method is confirmed in one-dimensional systems, it can be easily extended to higher dimensional systems.

Analysis of Subthreshold Swing for Double Gate MOSFET Using Gaussian Function (가우스함수를 이용한 DGMOSFET의 문턱전압이하 스윙분석)

  • Jung, Hak-Kee;Han, Ji-Hyung;Lee, Jae-Hyung;Jeong, Dong-Soo;Lee, Jong-In;Kwon, Oh-Shin
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2011.05a
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    • pp.681-684
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    • 2011
  • In this paper, the relationship of potential and charge distribution in channel for double gate(DG) MOSFET has been derived from Poisson's equation using Gaussian function. The subthreshold swing has been investigated according to projected range and standard projected deviation, variables of Gaussian function. The analytical potential distribution model has been derived from Poisson's equation, and subthreshold swing has been obtained from this model. The subthreshold swing has been defined as the derivative of gate voltage to drain current and is theoretically minimum of 60mS/dec, and very important factor in digital application. Those results of this potential model are compared with those of numerical simulation to verify this model. As a result, since potential model presented in this paper is good agreement with numerical model, the subthreshold swings have been analyzed according to the shape of Gaussian function.

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Efficient Learning Algorithm using Structural Hybrid of Multilayer Neural Networks and Gaussian Potential Function Networks (다층 신경회로망과 가우시안 포텐샬 함수 네트워크의 구조적 결합을 이용한 효율적인 학습 방법)

  • 박상봉;박래정;박철훈
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.12
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    • pp.2418-2425
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    • 1994
  • Although the error backpropagation(EBP) algorithm based on the gradient descent method is a widely-used learning algorithm of neural networks, learning sometimes takes a long time to acquire accuracy. This paper develops a novel learning method to alleviate the problems of EBP algorithm such as local minima, slow speed, and size of structure and thus to improve performance by adopting other new networks. Gaussian Potential Function networks(GPFN), in parallel with multilayer neural networks. Empirical simulations show the efficacy of the proposed algorithm in function approximation, which enables us to train networks faster with the better generalization capabilities.

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Modeling Charge Penetration Effects in Water-Water Interactions

  • Choi, Tae Hoon
    • Bulletin of the Korean Chemical Society
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    • v.35 no.10
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    • pp.2906-2910
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    • 2014
  • This report introduces Gaussian electrostatic models (GEMs) to account for charge penetration effects in water-water interactions, allowing electrostatic interactions to be accurately described. Three different Gaussian electrostatic models, GEM-3S, GEM-5S, and GEM-6S are designed with s-type Gaussian functions. The coefficients and exponents of the Gaussian functions are optimized using the electrostatic potential (ESP) fitting procedure based on that of the MP2/aug-cc-pVTZ method. The electrostatic energies of ten different water dimers that were calculated with GEM-6S agree well with the results of symmetry-adapted perturbation theory (SAPT), indicating that this designed model can be effectively applied to future water models.

Analysis of Channel Doping Profile Dependent Threshold Voltage Characteristics for Double Gate MOSFET (이중게이트 MOSFET에서 채널도핑분포의 형태에 따른 문턱전압특성분석)

  • Jung, Hak-Kee;Han, Ji-Hyung;Lee, Jae-Hyung;Jeong, Dong-Soo;Lee, Jong-In;Kwon, Oh-Shin
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.6
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    • pp.1338-1342
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    • 2011
  • In this paper, threshold voltage characteristics have been analyzed as one of short channel effects occurred in double gate(DG)MOSFET to be next-generation devices. The Gaussian function to be nearly experimental distribution has been used as carrier distribution to solve Poisson's equation, and threshold voltage has been investigated according to projected range and standard projected deviation, variables of Gaussian function. The analytical potential distribution model has been derived from Poisson's equation, and threshold voltage has been obtained from this model. Since threshold voltage has been defined as gate voltage when surface potential is twice of Fermi potential, threshold voltage has been derived from analytical model of surface potential. Those results of this potential model are compared with those of numerical simulation to verify this model. As a result, since potential model presented in this paper is good agreement with numerical model, the threshold voltage characteristics have been considered according to the doping profile of DGMOSFET.

Analysis of Subthreshold Current Deviation for Gate Oxide Thickness of Double Gate MOSFET (게이트 산화막 두께에 따른 이중게이트 MOSFET의 문턱전압이하 전류 변화 분석)

  • Jung, Hakkee;Jeong, Dongsoo;Lee, Jong-In;Kwon, Oshin
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.05a
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    • pp.762-765
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    • 2013
  • This paper analyzed the change of subthreshold current for gate oxide thickness of double gate(DG) MOSFET. Poisson's equation had been used to analyze the potential distribution in channel, and Gaussian function had been used as carrier distribution. The potential distribution was obtained as the analytical function of channel dimension, using the boundary condition. The subthreshold current had been analyzed for gate oxide thickness, and projected range and standard projected deviation of Gaussian function. Since this analytical potential model was verified in the previous papers, we used this model to analyze the subthreshold current. Resultly, we know the subthreshold current was influenced on parameters of Gaussian function and gate oxide thickness for DGMOSFET.

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