The zitterbewegung is an ultrafast oscillatory motion of a free electron was predicted by Erwin Schrödinger 1930 after studying the Dirac equation for an electron. Acting without any force, the electron changes its velocity, which contradicts Newton's second law of classical mechanics. Study this phenomenon experimentally and practically impossible to measure this effect is destroyed. Everyone believes that it is valid as well as the simulations show (Classical) computer. A new experiment Gerritsma et al. published in Nature has done a quantum simulation of such phenomena (studied a zitterbewegung analogous to a quantum system). This could not have used an ion (atomic calcium 40Ca +) trapped in an electromagnetic cavity (called a trap of Paul) which simulates a free particle Dirac (electron) and showed an oscillatory motion faster than interpreted as analog zitterbewegung a electron. The quantum simulation of quantum systems required to faithfully reproduce the Hamiltonian (the mathematical entity that represents the dynamic properties of the system) system quantum simulation. Gerritsma et al. We used two internal energy states of the ion to represent the states of positive and negative energy of a relativistic free electron, and the position and momentum of trapped ions to simulate the position and momentum of the free electron. By irradiation with laser light has been made that the ion moves in a way that simulates the Hamiltonian one-dimensional electron Dirac equation. By varying the laser intensity and frequency, Gerritsma et al. have managed to change the effective mass Dirac particle simulated the speed of light "effective" in the Dirac equation (which is important to model the amplitude zitterbewegung oscillations). In this way have been able to control this phenomenon by making it appear and disappear at convenience. Furthermore, they have shown that both non-relativistic limit (a very large effective mass) and in the ultrarelativistic (a very small effective mass) the zitterbewegung disappears, while the regime meets the observed phenomenon with theoretical expectations.
Dirac equation for the electron made several predictions that have been confirmed experimentally, the most dramatic prediction of antimatter (the anti-electron or positron), although other predictions have not been able to verify, as the paradox Klein or Schrödinger zitterbewegung. The origin of this latter phenomenon is the quantum interference between electron states with positive and negative energy. A free electron, not subject to any force, suffers from this phenomenon that changes its speed, contradict Newton's second law of classical mechanics. The simulation of Gerritsma et al. beautifully shows an example of the most important application of quantum computers (universal), to simulate other quantum systems. In this sense, his article is an important advance in research in quantum information systems.
For a free electron, the Dirac equation zitterbewegung effect predicts an amplitude of the order of the Compton length, RZB ≈ 10-12 m, and a frequency of 1021 Hz ≈ ωZB therefore escapes the effect of any direct measurement. The figure that opens this post shows the results obtained in the quantum simulation. The continuous curves are the results of computer simulations and numerical symbols represent data obtained by the experimental quantum simulation. The straight line (red squares) represents a massless particle (Ω = 0) moving at the speed of light "effective" (c = 2η Δ Δ = 0.052 ms-1). The other curves show increasing mass particles whose Compton wavelength is given by λC ≡ η Δ 2 / Δ Ω = 5.4 (triangles down), 2.5 Δ (diamonds), 1.2 Δ (circles) and 0.6 Δ (triangles into above), respectively. The figure clearly shows the zitterbewegung in the relativistic limit and how it disappears in the nonrelativistic limit. The figure below shows the results of numerical simulations for the wave functions (biespinor) representing the positive energy (spinor in blue) and the negative energy (red spinor) whose interference gives rise to zitterbewegung. This phenomenon requires both spinor wave function ψ (x) 2 are in phase, but the phenomenon is reduced until it vanishes when both parties are propagated in opposite directions.
From:
http://francisthemulenews.wordpress.com/2010/01/07/publicado-en-nature-simulacion-cuantica-del-zitterbewegung-de-un-electron-utilizando-un-ion-atrapado/
Dirac equation for the electron made several predictions that have been confirmed experimentally, the most dramatic prediction of antimatter (the anti-electron or positron), although other predictions have not been able to verify, as the paradox Klein or Schrödinger zitterbewegung. The origin of this latter phenomenon is the quantum interference between electron states with positive and negative energy. A free electron, not subject to any force, suffers from this phenomenon that changes its speed, contradict Newton's second law of classical mechanics. The simulation of Gerritsma et al. beautifully shows an example of the most important application of quantum computers (universal), to simulate other quantum systems. In this sense, his article is an important advance in research in quantum information systems.
For a free electron, the Dirac equation zitterbewegung effect predicts an amplitude of the order of the Compton length, RZB ≈ 10-12 m, and a frequency of 1021 Hz ≈ ωZB therefore escapes the effect of any direct measurement. The figure that opens this post shows the results obtained in the quantum simulation. The continuous curves are the results of computer simulations and numerical symbols represent data obtained by the experimental quantum simulation. The straight line (red squares) represents a massless particle (Ω = 0) moving at the speed of light "effective" (c = 2η Δ Δ = 0.052 ms-1). The other curves show increasing mass particles whose Compton wavelength is given by λC ≡ η Δ 2 / Δ Ω = 5.4 (triangles down), 2.5 Δ (diamonds), 1.2 Δ (circles) and 0.6 Δ (triangles into above), respectively. The figure clearly shows the zitterbewegung in the relativistic limit and how it disappears in the nonrelativistic limit. The figure below shows the results of numerical simulations for the wave functions (biespinor) representing the positive energy (spinor in blue) and the negative energy (red spinor) whose interference gives rise to zitterbewegung. This phenomenon requires both spinor wave function ψ (x) 2 are in phase, but the phenomenon is reduced until it vanishes when both parties are propagated in opposite directions.
From:
http://francisthemulenews.wordpress.com/2010/01/07/publicado-en-nature-simulacion-cuantica-del-zitterbewegung-de-un-electron-utilizando-un-ion-atrapado/
0 comments:
Post a Comment