共查询到20条相似文献,搜索用时 15 毫秒
1.
For a mesoscopic L-C circuit, besides the Louisell's quantization scheme in which electric charge q and electric current I are respectively quantized as the coordinate operator Q and momentum
operator P, in this paper we propose a new quantization scheme in the
context of number-phase quantization through the standard Lagrangian
formalism. The comparison between this number-phase quantization with the
Josephson junction's Cooper pair number-phase-difference quantization
scheme is made. 相似文献
2.
Shuai Wang 《International Journal of Theoretical Physics》2009,48(5):1459-1465
For L-C circuit, a new quantized scheme has been proposed in the context of number-phase quantization. In this quantization
scheme, the number n of the electric charge q(q=en) is quantized as the charge number operator and the phase difference θ across the capacity is quantized as phase operator. Based on the scheme of number-phase quantization and the thermo field
dynamics (TFD), the quantum fluctuations of the charge number and phase difference of a mesoscopic L-C circuit in the thermal
vacuum state, the thermal coherent state and the thermal squeezed state have been studied. It is shown that these quantum
fluctuations of the charge number and phase difference are related to not only the parameters of circuit, the squeezing parameter,
but also the temperature in these quantum states. It is proven that the number-phase quantization scheme is very useful to
tackle with quantization of some mesoscopic electric circuits and the quantum effects. 相似文献
3.
Bao-Long Liang Ji-Suo Wang Xiang-Guo Meng 《International Journal of Theoretical Physics》2007,46(11):2901-2909
The number-phase quantization scheme of the capacitance coupling double Josephson junction mesoscopic circuit is given. The
eigenvalues and the eigenstates of the system are investigated. It is found that using this system the entangled states can
be prepared. 相似文献
4.
Modified Josephson Equation for Mesoscopic Parallel LC Circuit Including a Josephson Junction 下载免费PDF全文
By introducing the entangled state representation, parallel LC circuit including a 3osephson junction equation associated with the modification of the motion equation. the Cooper-pair number-phase quantization of the mesoscopic is realized. In the Heisenberg picture, the modified Josephson Faraday equation about the inductance is deduced from the 相似文献
5.
量子计算如何在实验上实现一直受到广泛关注. 包括超导Josephson结的小量子器件(如超导量子干涉仪, SQUID)是实现量子计算的一种非常具有发展前景的物理系统. 本文通过对SQUID和介观LC共振器耦合电路系统的Cooper对数-相量子化机制的讨论, 合理地调制参数, 由此导出了该耦合电路在两能级近似下的J-C模型形式, 并提出了一种基于此模型的可实现量子信息传递的方案. 根据此方案可以利用介观LC共振器为数据总线来执行两SQUID间电荷量子比特的传递. 相似文献
6.
Cooper-Pair Number-Phase Quantization for a Mesoscopic LC Circuit Including a Josephson Junction 下载免费PDF全文
By introducing the entangled state representation and Feynman assumption that 'electron pairs are bosons, ..., a bound pair acts as a Bose particle ', we construct an operator Hamiltonian for a mesoscopic inductance-capacitance (LC) circuit including a Josephson junction, then we use the Heisenberg equation of motion to derive the current equation and the voltage equation across the inductance as well as across the Josephson junction. The result manifestly shows how the junction voltage is affected by the capacitance coupling. In this way the Cooper-pair number-phase quantization for this system is completed. 相似文献
7.
LIANG Bao-Long WANG Ji-Suo MENG Xiang-Guo 《理论物理通讯》2008,49(1):88-92
In this paper, the number-phase quantization scheme of the mesoscopic circuit, which consists of a singlequbit structure with superconducting quantum interference device coupled with a super-conducting resonator, is given. By introducing a unitary matrix and by means of spectral decomposition, the Hamiltonian operator of the system is exactly formulated in compact forms in spin-l/2 notation. The eigenvalues and the eigenstates of the system are investigated. It is found that using this system the entangled states can not only be prepared, but also be manipulated by tuning the magnetic flux through the super-conducting loop. 相似文献
8.
将介观并联RLC电路量子化,并利用幺正变换给出其波函数及能谱的精确解.在此基础上获得各支路中电流和电压的量子涨落.
关键词:
并联RLC电路
幺正变换
量子涨落 相似文献
9.
Number-Phase Quantization and Deriving Energy-Level Gap of Two LC Circuits with Mutual-Inductance 下载免费PDF全文
For two LC circuits with mutual-inductance, we introduce a new quantization scheme in the context of number- phase quantization through the standard Lagrangian formalism. The commutative relation between the charge operator and the magnetic flux operator is derived. Then we use the Heisenberg equation of motion to obtain the current and voltage equation across the inductance and capacity. The results clearly show how the current and voltage in a single LC circuit are affected by the circuit parameters and inductance coupling coettlcient. In addition, adopting invariant eigen-operator method the energy-level gap of the dynamic Hamiltonian which describes two LC circuits with mutual-inductance is obtained. 相似文献
10.
Bao-Long Liang Ji-Suo Wang Xiang-Guo Meng Jie Su 《International Journal of Theoretical Physics》2009,48(6):1545-1553
Via the Hamilton dynamical approach we have constructed Hamiltonian for the mutual inductance coupling magnetic flux qubits.
The entangled state representation is used to propose Cooper-pair number-phase quantization and the Hamiltonian operator for
the whole system. The dynamical evolution of the phase difference operator and the Cooper-pairs number operator is investigated
by virtue of Heisenberg equations.
Project 10574060 supported by the National Natural Science Foundation of China and project X071045 supported by the Science
Foundation of Liaocheng University. 相似文献
11.
The mesoscopic nonlinearinductance-capacitance circuit is a typical anharmonicoscillator, due to diodes included in the circuit. In this paper, using the advanced quantum theory of mesoscopic circuits, which based on the fundamental fact that the electric charge takes discrete value, the diode included mesoscopic circuit is firstly studied. Schrödinger equation of the system is a four-order difference equation in \hat{p} representation.Using the extended perturbative method, the detail energy spectrumand wave functions are obtained and verified, as an application ofthe results, the current quantum fluctuation in the ground state iscalculated. Diode is a basis component in a circuit, its quantization would popularize the quantum theory of mesoscopic circuits. The methods to solve the high order difference equation are helpful to the application of mesoscopic quantum theory. 相似文献
12.
13.
For an harmonic oscillator with a field intensity related external source we establish the nonlinear number-phase squeezed state, in this state we find that while the number fluctuation increases, the phase fluctuation decreases correspondingly. The number-phase uncertainty relationship is exactly derived. In contrast to the usual coherent state which makes up the minimum number-phase uncertainty relationship, the nonlinear number-phase squeezed state does not reach its minimum uncertainty. 相似文献
14.
Kopnin NB Mel'nikov AS Pozdnyakova VI Ryzhov DA Shereshevskii IA Vinokur VM 《Physical review letters》2005,95(19):197002
The interplay of geometrical and Andreev quantization in mesoscopic superconductors leads to giant mesoscopic oscillations of energy levels as functions of the Fermi momentum and/or sample size. Quantization rules are formulated for closed quasiparticle trajectories in the presence of normal scattering at the sample boundaries. Two generic examples of mesoscopic systems are studied: (i) one-dimensional Andreev states in a quantum box and (ii) a single vortex in a mesoscopic cylinder. 相似文献
15.
Xiu-Xia Wang 《International Journal of Theoretical Physics》2014,53(9):3164-3172
Using the IWOP technique, Wigner function theory and TFD theory, the quantization of a mesoscopic biological cell equivalent circuit is proposed, The quantum fluctuations of the mesoscopic biological cell are researched in thermal vacuum state and vacuum state. It is shown that the IWOP technique, Wigner function theory and Umezawa-Takahashi’s TFD theory play the key role in quantizing a mesoscopic biological cell at finite temperature and the fluctuations and uncertainty increase with increasing temperature and decrease with prolonged time. 相似文献
16.
电荷不连续时电容耦合介观电路的量子回路方程及其能谱 总被引:11,自引:0,他引:11
考虑电荷具有不连续性的事实对双LC介观电路进行量子化,给出耦合形式的量子回路方程以及无相互作用Hamilton本征基矢下的电路能谱.结果表明,计及电荷离散性将使回路方程的形式发生明显变化;介观电路的能谱除与电路参数相关外,还明显地依赖于电荷的量子化性质. 相似文献
17.
The quantization of resistances in the quantum Hall effect and ballistic transport through quantum point contacts is compared
with the quantization of the charge relaxation resistance of a coherent mesoscopic capacitor. While the former two require
the existence of a perfectly transmitting channel, the charge relaxation resistance remains quantized for arbitrary backscattering.
The quantum Hall effect and the quantum point contact require only local phase coherence. In contrast quantization of the
charge relaxation resistance requires global phase coherence. 相似文献
18.
19.
The importance of discreteness of electron charge for mesoscopic electric circuit is addressed. A quantization bf the circuit in accord with the discreteness of electric charges is proposed, and a Schrödinger equation incharge representation'is obtained. The Schrödinger equation is turned to be Mathieu equation in'current representation', the wavefunction and energy spectrum can be solved exactly. The WKB solutions of the energy levels for the ground state and the excited states are given. 相似文献