ترغب بنشر مسار تعليمي؟ اضغط هنا

Experimental demonstration of classical Hamiltonian monodromy in the 1:1:2 resonant elastic pendulum

592   0   0.0 ( 0 )
 نشر من قبل Noah Fitch
 تاريخ النشر 2009
  مجال البحث فيزياء
والبحث باللغة English




اسأل ChatGPT حول البحث

The 1:1:2 resonant elastic pendulum is a simple classical system that displays the phenomenon known as Hamiltonian monodromy. With suitable initial conditions, the system oscillates between nearly pure springing and nearly pure elliptical-swinging motions, with sequential major axes displaying a stepwise precession. The physical consequence of monodromy is that this stepwise precession is given by a smooth but multivalued function of the constants of motion. We experimentally explore this multivalued behavior. To our knowledge, this is the first experimental demonstration of classical monodromy.



قيم البحث

اقرأ أيضاً

We consider integrable Hamiltonian systems in three degrees of freedom near an elliptic equilibrium in 1:1:-2 resonance. The integrability originates from averaging along the periodic motion of the quadratic part and an imposed rotational symmetry ab out the vertical axis. Introducing a detuning parameter we find a rich bifurcation diagram, containing three parabolas of Hamiltonian Hopf bifurcations that join at the origin. We describe the monodromy of the resulting ramified 3-torus bundle as variation of the detuning parameter lets the system pass through 1:1:-2 resonance.
181 - S. Filipp , J. Klepp , Y. Hasegawa 2008
The geometric phase has been proposed as a candidate for noise resilient coherent manipulation of fragile quantum systems. Since it is determined only by the path of the quantum state, the presence of noise fluctuations affects the geometric phase in a different way than the dynamical phase. We have experimentally tested the robustness of Berrys geometric phase for spin-1/2 particles in a cyclically varying magnetic field. Using trapped polarized ultra-cold neutrons it is demonstrated that the geometric phase contributions to dephasing due to adiabatic field fluctuations vanish for long evolution times.
We report on the anomalously high line strength of a single rotational level in the ultracold photoassociation of two 85Rb atoms to form 85Rb2. The v = 111, J = 5 level belongs to the Hunds case (c) 2 (0g+) state, which correlates to the Hunds case ( a) 2 1 Sigma g+ state. Its strength is caused by coupling with a very near-resonant long-range state. The long-range component is the energetically degenerate v = 155, J = 5 level of the case (c) 2 (1g)$ state, correlating to the case (a) 1 1 Pi g state. The line strength is enhanced by an order of magnitude through this coupling, relative to nearby vibrational levels and even to nearby rotational levels of the same vibrational level. This enhancement is in addition to the enhancement seen in all J = 3 and 5 levels of the 2 (0g+) state due to an l = 4 shape resonance in the a 3 Sigma u+ state continuum, which alters the distribution of levels formed by photoassociation.
We report on the sub-Doppler laser cooling of neutral $^{171}$Yb and $^{173}$Yb in a magneto-optical trap using the $^{1}S_{0}$-$^{1}P_{1}$ transition at 398.9nm. We use two independent means to estimate the temperature of the atomic cloud for severa l of the Yb isotopes. The two methods of MOT-cloud-imaging and release-and-recapture show consistency with one another. Temperatures below 400$mu$K and 200$mu$K are recorded for $^{171}$Yb and $^{173}$Yb, respectively, while ~1mK is measured for both $^{172}$Yb and $^{174}$Yb. By comparison, the associated 1D Doppler cooling temperature limit is 694$mu$K. The sub-Doppler cooling of the I=1/2 $^{171}$Yb isotope in a $sigma^{+}-sigma^{-}$ light-field trap adds further evidence that the Sisyphus cooling mechanism is occurring in such 3D magneto-optical traps.
146 - L. Aldridge , P. L. Gould , 2011
By combining a recent precise measurement of the ionization energy of $^{87}$Rb with previous measurements of electronic and hyperfine structure, an accurate value for the $^{85}textrm{Rb}-^{87}textrm{Rb}$ isotope shift of the 5$^2S_{1/2}$ ground sta te can be determined. In turn, comparison with additional spectroscopic data makes it possible for the first time to evaluate isotope shifts for the low-lying excited states, accurate in most cases to about 1 MHz. In a few cases, the specific mass shift contribution can be determined in addition to the total shift. This information is particularly useful for spectroscopic analysis of transitions to Rydberg states, and for tests of atomic theory.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا