Daniel Frank Walls

Daniel Walls
Born	1942 New Zealand
Died	12 May 1999 Auckland, New Zealand
Residence	New Zealand
Nationality	New Zealand
Fields	Physicist
Institutions	University of Auckland University of Waikato
Alma mater	Harvard University
Doctoral advisor	Roy J. Glauber
Doctoral students	Gerard J. Milburn Andrew C. Doherty Howard J. Carmichael Peter D. Drummond Craig M. Savage
Known for	Quantum optics
Notable awards	Dirac Medal (1995)

Daniel Walls (1942 - 1999) was a theoretical physicist specialising in quantum optics.

Dan Walls gained a BSc in physics and mathematics and a first class honours MSc in physics at the University of Auckland. He then went to Harvard as a Fulbright Scholar, obtaining his PhD in 1969, under Roy J. Glauber (who later won a Nobel prize). After holding post-doctoral positions in Auckland and Stuttgart, Walls became a senior lecturer in physics at the University of Waikato in 1972, where he became professor in 1980. In 1987 he moved to the University of Auckland as professor of theoretical physics.

His major research interests centered on the interaction and similarities between light and atoms. He was notable for his wide-ranging expertise in relating theory to experiment, and was involved in all major efforts to understand non-classical light. A seminal paper (J Phys B 9, 1199 (1976)) by Walls with his first graduate student Howard Carmichael, showed how to create antibunched light, in which photons arrive at regular intervals, rather than randomly.

He also was a pioneer in the study of ways that the particle-like nature of light (photons) could be controlled to make optical systems less susceptible to unwanted fluctuations, in particular by the use of squeezed light, a concept formulated by Carlton Caves. In squeezed light, some fluctuations can be made very small provided other fluctuations are correspondingly large.

He made major contributions to the theory of quantum measurement such as those involving Einstein's "which-path" experiment, and the quantum nondemolition measurement.

In the later stages of his career he focused his research efforts on the theoretical aspects of the newly created state of matter, the Bose-Einstein condensate (BECs). Some of his contributions in the field include the prediction of the interference signature of quantized vortices, and the collapses and revivals of the Josephson coupled BECs.

Dan Walls was made a Fellow of the Royal Society of London, an honor bestowed on just 37 New Zealand-born scientists since the Society's establishment in 1660, and a Fellow of numerous academic societies such as the American Physical Society and the Royal Society of New Zealand. His many medals and prizes included the award in 1995 of the Paul Dirac Medal for theoretical physics.

He died of cancer in hospital in Auckland, aged 57. ^[1]

1. ^ http://www.highbeam.com/doc/1P2-17393235.html

Persondata
Name	Walls, Daniel
Alternative names	Dan Walls
Short description	THE GORBALS physicist
Date of birth	19 September 1942
Place of birth	New Zealand
Date of death	1999
Place of death	Auckland, New Zealand