Stochastic Simulation of a Casimir Oscillator

Author(s):  
Farbod Khoshnoud ◽  
Houman Owhadi ◽  
Clarence W. de Silva

Stochastic simulation of a Casimir Oscillator is presented in this paper. This oscillator is composed of a flat boundary of semiconducting oscillator parallel to a fixed plate separated by vacuum. In this system the oscillating surface is attracted to the fixed plate by the Casimir effect, due to quantum fluctuations in the zero point electromagnetic field. Motion of the oscillating boundary is opposed by a spring. The stored potential energy in the spring is converted into kinetic energy when the spring force exceeds the Casimir force, which generates an oscillatory motion of the moving plate. Casimir Oscillators are used as micro-mechanical switches, sensors and actuators. In the present paper, a stochastic simulation of a Casimir oscillator is presented for the first time. In this simulation, Stochastic Variational Integrators using a Langevin equation, which describes Brownian motion, is considered. Formulations for Symplectic Euler, Constrained Symplectic Euler, Stormer-Verlet and RATTLE integrators are obtained and the Symplectic Euler case is solved numerically. When the moving parts in a micro/nano system travel in the vicinity of 10 nanometers to 1 micrometer range relative to other parts of the system, the Casimir phenomenon is in effect and should be considered in analysis and design of such system. The simulation in this paper considers modeling such uncertainties as friction, effect of surface roughness on the Casimir force, and change in environmental conditions such as ambient temperature. In this manner the paper explores a realistic model of the Casimir Oscillator. Furthermore, the presented study of this system provides a deeper understanding of the nature of the Casimir force.

2002 ◽  
Vol 11 (10) ◽  
pp. 1567-1572 ◽  
Author(s):  
FABRIZIO PINTO

In the typical Casimir effect, the boundaries of two semi-infinite media exert a force upon one another across a vacuum gap separating them. In this paper, I argue that a static gravitational field can be regarded as a "soft" boundary which interacts with a test object of finite size through the electromagnetic zero-point-energy field. Therefore, a pressure exists upon a single slab placed in a gravitational field and surrounded by a vacuum. Interestingly, this extremely small Casimir pressure of the gravitational field may cause relative displacements in ground-based sensing microstructures larger than those from astrophysical gravitational waves in macroscopic antennas.


2008 ◽  
Vol 63 (9) ◽  
pp. 571-574
Author(s):  
Frédéric Schuller

We tackle the very fundamental problem of zero-point energy divergence in the context of the Casimir effect. We calculate the Casimir force due to field fluctuations by using standard cavity radiation modes. The validity of convergence generation by means of an exponential energy cut-off factor is discussed in detail.


Author(s):  
Farbod Khoshnoud ◽  
Clarence W. de Silva ◽  
Houman Owhadi

Design and analysis of an embedded nano-electromechanical capacitive sensor for vibration monitoring is presented in this paper. In this sensor, vibration sensing is carried out by detecting the oscillations of a Single Walled Carbon Nanotube (SWCNT). The SWCNT is excited when it is subjected to a base motion corresponding to the measured vibration. Acquisition of the sensor signal is performed by a capacitance circuit, using the electric charge generated in the Carbon Nanotube (CNT). A modulation in the charge in the CNT, due to change in the capacitance, leads to a modulation in the CNT’s conductance and is used in measuring the input vibration. Vibration properties of the CNTs are obtained by molecular mechanics and finite element analysis where atoms are modeled as particles with an equilibrium distance equal to the bond length, and the bonded interactions of atoms are modeled as flexible beams. Stiffness coefficients of the atomic bonds are modeled using Morse atomic potential. A bridge circuit is utilized in this sensor to compensate for temperature and other environmental effects. When the CNT is in the vicinity of the gate underneath the tube, at a distance in the range of 1 nanometer to 1 micrometer, Casimir pressure, due to quantum fluctuations in the zero point electromagnetic field, can attract the CNT to the gate. This unwanted applied force on the tube may lead to inaccurate measurement of the vibration. In order to study the effect of Casimir pressure on the CNT a simplified model of the Casimir effect, for parallel surfaces, is adopted. This model can assist in achieving better accuracy in vibration measurement, and the sensor can be calibrated accordingly to account for the Casimir attractive force. The paper presents the physical and operational details of the sensor. This device is particularly useful for precise and effective sensing of vibration for machinery and structural condition monitoring and fault diagnosis.


2012 ◽  
Vol 14 ◽  
pp. 200-214
Author(s):  
V. M. MOSTEPANENKO ◽  
V. B. BEZERRA ◽  
G. L. KLIMCHITSKAYA ◽  
C. ROMERO

Measurements of the Casimir force are used to obtain stronger constraints on the parameters of hypothetical interactions predicted in different unification schemes beyond the Standard Model. We review new strong constraints on the Yukawa-type interactions derived during the last two years from recent experiments on measuring the lateral Casimir force, Casimir force in configurations with corrugated boundaries and the Casimir-Polder force. Specifically, from measurements of the lateral Casimir force compared with the exact theory the strengthening of constraints up to a factor of 24 millions was achieved. We also discuss further possibilities to strengthen constraints on the Yukawa interactions from the Casimir effect.


2017 ◽  
Vol 26 (12) ◽  
pp. 1743031 ◽  
Author(s):  
Nader A. Inan

The response of a superconductor to a gravitational wave is shown to obey a London-like constituent equation. The Cooper pairs are described by the Ginzburg–Landau free energy density embedded in curved spacetime. The lattice ions are modeled by quantum harmonic oscillators characterized by quasi-energy eigenvalues. This formulation is shown to predict a dynamical Casimir effect since the zero-point energy of the ionic lattice phonons is modulated by the gravitational wave. It is also shown that the response to a gravitational wave is far less for the Cooper pair density than for the ionic lattice. This predicts a “charge separation effect” which can be used to detect the passage of a gravitational wave.


1990 ◽  
Vol 68 (1) ◽  
pp. 91-95 ◽  
Author(s):  
T. F. Treml

The vacuum energy in interacting scalar field theory is computed in the case of the Casimir effect as a sum over zero-point energies and as a path-integral determinant, using both ζ-function regularization and dimensional regularization. Using a simple nonrecursive method of calculation, the two forms of the vacuum energy are shown to differ before renormalization by a scale-independent term when ζ-function regularization is used, but yield exactly the same result when dimensional regularization is used.


2016 ◽  
Vol 31 (06) ◽  
pp. 1650012
Author(s):  
Guglielmo Fucci

In this work, we analyze the Casimir energy and force for a thick piston configuration. This study is performed by utilizing the spectral zeta function regularization method. The results we obtain for the Casimir energy and force depend explicitly on the parameters that describe the general self-adjoint boundary conditions imposed. Numerical results for the Casimir force are provided for specific types of boundary conditions and are also compared to the corresponding force on an infinitely thin piston.


2006 ◽  
Vol 21 (25) ◽  
pp. 1957-1963 ◽  
Author(s):  
HONGBO CHENG

In this paper, the Casimir effect for parallel plates in the presence of one compactified universal extra dimension is re-examined in detail. Having regularized the expressions of Casimir force, we show that the nature of Casimir force is repulsive if the distance between the plates is large enough, which does not agree with the experimental phenomena.


2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Sébastien Léger ◽  
Javier Puertas-Martínez ◽  
Karthik Bharadwaj ◽  
Rémy Dassonneville ◽  
Jovian Delaforce ◽  
...  

AbstractElectromagnetic fields possess zero point fluctuations which lead to observable effects such as the Lamb shift and the Casimir effect. In the traditional quantum optics domain, these corrections remain perturbative due to the smallness of the fine structure constant. To provide a direct observation of non-perturbative effects driven by zero point fluctuations in an open quantum system we wire a highly non-linear Josephson junction to a high impedance transmission line, allowing large phase fluctuations across the junction. Consequently, the resonance of the former acquires a relative frequency shift that is orders of magnitude larger than for natural atoms. Detailed modeling confirms that this renormalization is non-linear and quantum. Remarkably, the junction transfers its non-linearity to about thirty environmental modes, a striking back-action effect that transcends the standard Caldeira-Leggett paradigm. This work opens many exciting prospects for longstanding quests such as the tailoring of many-body Hamiltonians in the strongly non-linear regime, the observation of Bloch oscillations, or the development of high-impedance qubits.


2020 ◽  
Vol 35 (03) ◽  
pp. 2040015 ◽  
Author(s):  
Valery N. Marachevsky

Casimir interaction of two SiO2 glass half spaces being substrates for Chern-Simons boundary layers is studied. The separation between two half spaces at which the Casimir energy minimum occurs is strongly increased for dielectric SiO2 glass substrates in comparison with previously considered metal Au and semiconductor Si substrates. Strong reduction in the Casimir force due to presence of Chern-Simons layers is found for SiO2 glass substrate. Influence of modification of the infrared absorption on the Casimir force is studied.


Sign in / Sign up

Export Citation Format

Share Document