Oscillating fields

A connnon teclmique used to enliance the signal-to-noise ratio for weak modes is to inject a local oscillator field polarized parallel to the RIKE field at the detector. This local oscillator field is derived from the probe laser and will add coherently to the RIKE field [96]. The relative phase of the local oscillator and the RIKE field is an important parameter in describing the optical heterodyne detected (OHD)-RIKES spectrum. If the local oscillator at the detector is in phase with the probe wave, the heterodyne mtensity is proportional to... 

The last attribute of tire electromagnetic field we need to discuss is wave polarization. The nature of tire transverse field is such tliat tire oscillating field disturbance (which is perjDendicular to tire propagation direction) has a particular orientation in space. The polarization of light is detennined by tire time evolution of tire direction of tire electric field... 

Since the charge becomes coupled with the oscillating field, q undergoes a periodic acceleration which we represent by ap. Next we borrow a relationship from electromagnetic theory to describe the field produced by an oscillating dipole such as the molecule we have described ... 

I should mention the convention that in electromagnetic studies we write oscillating fields as (e.g.) E = Eq expfjujf) rather than E = Eq cos(ju)f). There is nothing sinister in this—it just makes the maths simpler. A laboratory electric field is the real part of E = Eq exp(jujr), and so we have to remember to take the real part of any result before comparison with experiment. 

At these high frequencies, the retarding effect of the ion-atmosphere on the movement of a central ion is greatly decreased and conductance tends to be increased. The capacitance effect is related to the absorption of energy due to induced polarisation and the continuous re-alignment of electrically unsymmetrical molecules in the oscillating field. With electrolyte solutions of low dielectric constant, it is the conductance which is mainly affected, whilst in solutions of low conductance and high dielectric constant, the effect is mostly in relation to capacitance. 

Markin, V S. Thermodynamics of Membrane Energy Transduction in an Oscillating Field 24... 

Figure 4-1. Light as transverse electric ( ) and magnetic (5) oscillating fields normal to the propagation direction.

Transduction in an Oscillating Field Electric Breakdown in Anodic Oxide Films 23... 

This is equivalent to transformation into a coordinate system that rotates with the oscillating field u is that part of Mx which is in-phase with Bx and v is the part which is 90° out of phase. Differentiating eqn (5.11a) and substituting eqns (5.9a) and (5.9b), we get ... 

Notice that as B approaches zero, u and v go to zero and Mz approaches M0, as expected. That is, it is the transverse oscillating field that causes the magnetization to have a non-equilibrium value. On the other hand, as B increases, Mz decreases (moves away from equilibrium) u and v at first increase with increasing B, but eventually they decrease as the third term in the denominator begins to dominate. 

A beam of light consists of two mutually perpendicular oscillating fields an oscillating electric field and an oscillating magnetic field. 

Multiple-Oscillating Field Techniques Dipolar Truncation,... 

Multiple-Oscillating Field Techniques Dipolar Truncation, Recoupling of Native Dipolar Coupling, and Recoupling Without Decoupling... 

In an alternative approach, which as we shall see in this section also serves to improve on some of the other problems in addition to dipolar truncation, the groups of Khaneja and Nielsen introduced a novel approach for dipolar recoupling involving multiple-oscillating fields [46—49]. The first of these experiments involved the... 

As mentioned above, the concept of multiple-oscillating field techniques and symmetry-based dipolar recoupling has recently been merged in terms of the EXPORT-CN experiment offering new possibilities for low-power dipolar recoupling [132],... 

In the high-field limit (F > 1 atomic unit meaning that it is greater than the binding potential) the smoothed Coulomb potential in Eq. (2) can be treated as a perturbation on the regular, classical motion of a free electron in an oscillating field. So, let us first consider the Hamiltonian for the one-dimensional motion of a free electron in the... 

Fig. 17.9 Sketch of a typical setup for ion trap experiments on lasing microdroplets. The oscillating field between the inner and outer ring electrodes forms the trapping potential, and gravitational forces can he opposed by static electrical fields to move the droplet to the trap center with no micromotion...

A static electrical field in free space cannot have potential minima and hence cannot trap a charged particle. By using oscillating fields, a pseudopotential can be formed as illustrated in Fig. 17.8, where amass with a suitable charge to mass ratio can be trapped. 

In this way, we shall be able to calculate the Unear response of the system. For such a linear problem, we may as well consider an oscillating field with frequency w ... 

---