Quantum well excitons in semiconductor microcavities : unified treatment of weak and strong coupling regimes

Preface 1. Planck's radiation law and the Einstein coefficients 2. Quantum mechanics of the atom-radiation interaction 3. Classical theory of optical fluctuations and coherence 4. Quantization of the radiation field 5. Single-mode quantum optics 6. Multimode and continuous-mode quantum optics 7. Optical generation, attenuation and amplification 8. Resonance fluorescence and light scattering 9. Nonlinear quantum optics Index

The quantum theory of light.

Quantum theory of the lossless beam splitter

This chapter discusses the quantum Zeno and inverse quantum Zeno effects The quantum Zeno effect is a consequence of the new dynamical features introduced by a series of measurement processes In turn, a measurement process is because of the coupling with an external apparatus that, after interacting with the system, gets entangled with it The quantum Zeno effect is explained in terms of the Schrodinger equation, without making use of projection operators The chapter considers a two-level system undergoing Rabi oscillations A quantum-mechanical measurement is a complicated physical process, taking place in a finite time and involving complex (macroscopic) physical systems A down-conversion process in a nonlinear crystal is the decay of a pump photon into a pair of signal and idler photons of lower frequency The differences and analogies between pulsed and continuous observations analyzed are discussed by considering a quantum optical example

Chapter 3 Quantum Zeno and inverse quantum Zeno effects

A quantum-statistical description of noise in interferometers is given in terms of the Wigner distribution function. The interferometer may contain an amplifier in one of its arms. The input field can be in a variety of states such as a Fock state, a coherent state or a squeezed coherent state. The Wigner function of the output field at the detector is shown to have a general Gaussian form with non-zero complex field amplitude and with other parameters related to the characteristics of the input field, amplifier and beam splitters, etc. An explicit form of the photon-number distribution is given. Higher-order correlations of the output field can be obtained from the Gaussian property of the Wigner function.

Wigner-function Description of Quantum Noise in Interferometers

The quantum limits on measurements of small changes in the length of a Fabry-Perot cavity are calculated. The cavity is modelled by a pair of dissimilar mirrors oriented perpendicular to a one-dimensional axis of infinite extent. The continuous spectrum of spatial modes of the system is derived, and the electromagnetic field is quantized in terms of a continuous set of mode creation and destruction operators. Coherent state and squeezed vacuum-state excitations of the field are characterized by energy flow, or intensity, variables. The determination of small changes in the cavity length by observations of fringe intensity is considered for schemes in which the cavity is simultaneously excited by coherent and squeezed vacuum-state inputs. The contributions to the limiting resolution from photocount and radiation-pressure length uncertainties are evaluated. These properties of the Fabry-Perot cavity are compared with the corresponding results for the Michelson interferometer.

http://baton.phys.lsu.edu/~jdowling/PHYS7353/lectures/Ley87.pdf

Quantum theory of high-resolution length measurement with a Fabry-Perot interferometer

Expressions are derived for the density matrix elements appropriate to single-quantum excitation of the two arms of optical interferometers where an amplifier is inserted into one of the arms. The ...

M. Ley

Papers

Quantum theory of high-resolution length measurement with a Fabry-Perot interferometer

Theory of Single-photon Interference Experiments