Quantum Paths

Festschrift in Honor of Berge Englert on His 60th Birthday

Hui Khoon Ng, Rui Han

• Publisher: WSPC
• Year: 2015
• ISBN:
  9789814651851
• Topic: Storia
• Subtopic: Storia della scienza

This volume is a collection of original articles or reprints of journal papers and book chapters written or inspired by Berge Englert, as well as essays recounting Professor Englert's impact on all the contributors' scientific careers and lives in general. The scientific articles span a wide range of topics in quantum physics — from quantum optics, foundations of quantum physics, to quantum information — reflecting his influential impact. The personal essays offer a rare insight into the man behind the science — the essence of who he is. Each article in the book is preceded by a commentary from the contributor who wrote or suggested the inclusion of the article, highlighting its significance. The collection was created in relation to a conference, BergeFest, held in UTown, National University of Singapore, in April 2014, in celebration of the 60th birthday of Professor Berge Englert.

This volume is a collection of original articles or reprints of journal papers and book chapters written or inspired by Berge Englert, as well as essays recounting Professor Englert's impact on all the contributors' scientific careers and lives in general. The scientific articles span a wide range of topics in quantum physics — from quantum optics, foundations of quantum physics, to quantum information — reflecting his influential impact. The personal essays offer a rare insight into the man behind the science — the essence of who he is. Each article in the book is preceded by a commentary from the contributor who wrote or suggested the inclusion of the article, highlighting its significance. The collection was created in relation to a conference, BergeFest, held in UTown, National University of Singapore, in April 2014, in celebration of the 60th birthday of Professor Berge Englert.

Readership: Researchers and graduate students working in the field of quantum mechanics and quantum information. Key Features:

• Prof. Englert is unique in his own way
• Contributors are well-known physicists, which should attract much readership
• Many people study quantum mechanics and quantum information so it will be relevant to them

Chapter 1

Quantum Optics and Open Quantum Systems

Hans Briegel

Institut für Quantenoptik und Quanteninformation der Österreichischen Akademie der Wissenschaften, Innsbruck, Austria

Institut für Theoretische Physik, Universität Innsbruck, Innsbruck, Austria

Paper Title: Quantum optical master equations: The use of damping bases

Reference: Physical Review A 47, 3311–3329 (1993)

Personal message:

This damping-bases paper was one of my first papers with Berge, who was my PhD supervisor and who introduced me to the field of quantum optics.

The paper introduced a new method for solving master equations that appear in quantum optics. It contains the full analytical solution of the “Jaynes-Cummings model with damping”, which describes the interaction of a single atom with a quantized mode of the cavity field, when the field and the atom are subjected to damping and spontaneous decay, respectively. This model played an important role in cavity QED experiments and in the micromaser, which were studied at that time in the groups of Herbert Walther at MPQ in Garching and Serge Haroche at ENS in Paris. The paper became a starting point for a series of theoretical investigations of the micromaser. It allowed us, for example, to exactly compute the quantum state of the laser field under realistic experimental conditions, and to analyze the effect of non-Poissonian pumping on the laser field and its spectrum. It also enabled us to predict the properties of a single-atom laser and to explain the effect of dynamic noise reduction in lasers with multi-level pumping. Beyond laser physics and quantum optics, the damping bases method has seen many other applications, most recently in quantum information and in the analysis of quantum channels with memory.

Since there is only limited space in this Festschrift, I leave it to the editors to deal with a problem that Berge and I never addressed (and, fortunately, did not even think of), namely, how to shorten or compress this paper to the usual four pages ... (Editors’ note: Since there is no need to subscribe to the illustrious 4-page limit here, we have included the 19-page article in its entirety, trusting readers to appreciate the deeper understanding one gains from the additional details, and not mind the extra weight of those 15 pages.)

Dear Berge,

You were a marvelous teacher and supervisor. I felt very proud and I was very lucky that you accepted me as your first PhD student. Working with you was a unique experience and rewarding in every respect. I don’t remember any meeting with you which would not result in a new insight, a helpful calculation, or a useful advice that guided me in the right direction. Also from a personal perspective, the PhD was a very special time of my life. Working at the Coulombwall in Garching, with my desk facing towards the Isar meadows, I could experience theoretical research as it ought to be, with enough time to think and deeply concentrate on a problem. I was happy to have you next door, not only for advice, but also to bring me occasionally back down to Earth and go for a Leberkäs at the Cafeteria in the TU Mensa.

Thank you for this wonderful time, for our collaborations, and for your friendship. Happy Birthday!

With best wishes,

Hans

PHYSICAL REVIEW A

VOLUME 47, NUMBER 4

APRIL 1993

Quantum optical master equations: The use of damping bases

Hans-Jürgen Briegel and Berthold-Georg Englert*

Sektion Physik, Universität München, Am Coulombwall 1, D-8046 Garching, Germany

(Received 21 July 1992)

We present the complete analytical solution of the cavity QED of a two-level atom and a field mode at zero temperature. It includes both dissipation of the field due to a finite Q value of the cavity and incoherent decay mechanisms for the atom. This analytical solution is provided by a powerful method for treating general master equations that appear in quantum optics. As distinct ...