J. Gea-Banacloche

Soft X-Ray free-electron laser with a laser undulator

We discuss the possibility of building a free-electron laser in the spectral region of tens of nanometers using a high-power laser pulse as the undulator. Requirements on the electron beam emittance, brightness, and energy spread are derived. The possibility of operation at the quantum limit is considered. The reduction of the gain due to diffraction of the undulator pulse (the variable mass-shift effect) is investigated, and several ways in which it could be overcome are suggested. Examples are presented showing that the device is feasible with moderate advances in current electron injector technology. Such a device would not require a large accelerator for high electron energies, nor a long wiggler made of permanent magnets.

Laser cavity dumping using optical bistability

Abstract In this paper we present a scheme for passive cavity dumping of a laser. The basic idea is to replace one of the laser mirrors with an optically bistable element. The cases of operation with absorptive and dispersive bistable elements are analyzed.

Free electron lasers in the x‐ray region

An x‐ray free‐electron laser (FEL) must operate with large gain per pass because of the poor quality of available mirrors at x‐ray frequencies. Moreover, the effects of inhomogeneous broadening, start‐up from noise, coherence development, and quantum recoil can be important in determining whether and how such devices will operate. We present a one‐dimensional analysis of the gain regimes for x‐ray FEL’s and consider the example of a 5A FEL operating with a uniform wiggler of wavelength 3.2 cm. We also estimate constraints on such a device imposed by effects such as diffractive spreading of the laser beam, energy spread and emittance of the electron beam, and transverse variations in the wiggler field.

CEL gyroscope with injected squeezed vacuum

It is shown that the injection of a squeezed vacuum into a correlated emission ring laser gyroscope enhances the sensitivity of the device. In particular, it is demonstrated that if the phase of the injected squeezed vacuum is chosen appropriately, then the output is squeezed in the phase quadrature. This may lead to complete suppression of the shot noise in the signal.

Tests of General Relativity and the Correlated Emission Laser

The arena of space-time and metric gravity is a grand playground for modern quantum optical scientists. Work in this field defines the cutting edge of technology, from precision interferometry to the quantum “limits” of measurement.

Quantum Theory of the Free-Electron Laser

In this paper we consider the main reasons why a quantum theory of the free-electron laser is of interest, and summarize and compare a number of different approaches, and their main results. Recent results concerning the intrinsic linewidth and photon statistics of the free-electron laser are also presented.

Quantum theory of the free electron laser in the laboratory frame

Abstract We have developed a formalism that allows us to use ordinary quantum mechanics (instead of quantum electrodynamics) to study the FEL in the laboratory frame. In this paper, we apply that formalism to the study of spontaneous emission and the growth of coherence in the linear (small-signal) regime, via a multimode calculation. We also present single-mode results concerning the effect of quantum-mechanical corrections to the gain and the saturation. Finally, we review the question of photon statistics; an extension of earlier results is pointed out.

Stimulated Synchrotron Radiation: The Free-Electron Laser

The free-electron laser is one of the most recent sources of coherent radiation. Its operation was first demonstrated at Stanford, by Madey and co-workers [1], using an electron beam from the Stanford linear superconducting accelerator; the laser wavelength in this experiment was 3.4 μm. Since then, free-electron lasers have been operated at Orsay (using a storage ring, at a laser wavelength tunable between 6350 and 6600 A)[2], Los Alamos (using a linear accelerator, at wavelengths between 9 and 11 μm) [3a], and the University of California at Santa Barbara (using a Van der Graaf electrostatic accelerator, at a wavelength of 380 μm) [3b]. (A list of proposed experiments may be found in [4]).

Phase Transition Analogies: Magnets, Lasers and Fluid Flows

One of the early developments of the quantum theory of a laser vas the uncovering of a striking similarity between the behavior of a laser around threshold and a second-order phase transition such as the order-disorder transitions of ferromagnetic and superfluid systems /1, 2/. The analogy was soon extended to a variety of phenomena in quantum optics, such as the symmetry broken laser (laser with injected signal /1 /, lasers with saturable absorbers /3 /, optical bistability /4/and transient processes such as superfluorescence. Recently, the analogy has been extended in a bold though useful approach to hydrodynamic instabilities /5–8/. Such studies provided useful insights into the statistical mechanics of systems operating far from thermodynamic equilibrium and permitted the uncovering of fascinating phenomena in otherwise unrelated fields.