There has been great advancement in the field of laser science and technology with wide applications which has led to several Noble Prize awards in recent years in Physics and Chemistry. Lasers are being developed from femto to atto-second range enabling scientists in the study of phenomena on the time scale of electron motion in atoms and molecules. Consequently, other interesting areas of scientific study include solid state, plasma physics, nano-science and defence technology. Lasers also permit us to reach exceedingly low temperatures often less than a billionth of a degree above absolute zero which includes the implications of Bose-Einstein condensation (BEC), fermionic superfluidity etc. Initially, the focus on BEC was on the study of basic properties such as superfluidity, structural properties, collective and elementary excitations, vortices, light matter interactions etc. But in recent years, the focus has shifted to some important applications such as detection of weak forces, cavity electrodynamics and opto-mechanics.

The book describes some of the latest advances in laser physics and technology and its applications. The book is divided into five major sections: Laser Processes Involving Short Pulses, Laser Spectroscopy, Laser Cooling and Trapping, Quantum Optics and Laser Applications.

The first section deals with the laser processes in atoms and molecules involving short pulse lasers. It contains topics from high-harmonic generation (HHG) and strong-field non-sequential double ionization (NSDI), with emphasis on atto-second orbital imaging to the field of molecular quantum computing including a description of all current theoretical and experimental results. Chapter 1, Augstein et al., addresses high harmonic generation (HHG) and strong-field non-sequential double ionization (NSDI), with emphasis on atto-second orbital imaging. In Chapter 2, Alex Brown et al., a general introduction is given to the field of molecular quantum computing including a description of all current theoretical and experimental results. These chapters enumerate the laser requirements and molecular properties that govern the implementation of high-fidelity quantum gates.

The effect of a low energy atto-second pulse sustaining only a few-cycles is studied in Chapter 3, on a simple two-level system for different pulse envelope profiles. An atto-second pulse, due to its very short duration, can be sustained only by wavelengths of hundreds of angstroms. Such pulses are highly energetic and can cause molecular dissociation.