Vol.2, No 1, 1999 pp. 31 - 38
UDC 514.84

BOSON BOGOLIUBOV GROUP
AND GENERALIZED SQUEEZED STATES
I. Mendaš1, M. J. Djordjević2
1Institute of Physics, P.O. Box 57, 11001 Belgrade,Yugoslavia
2Faculty of Physics, University of Belgrade, P.O. Box 386, 11001 Belgrade, Yugoslavia

Abstract. A convenient choice of the arbitrary phase of the Bogoliubov unitary operator, providing the homogeneous Bogoliubov transformation of the boson annihilation and creation operators, is proposed so that the Bogoliubov transformations form a continuos non-Abelian subgroup of the SL(2,C) group. Two operator identities involving this Bogoliubov operator are established and, with their help, the closed form expressions for the correlation amplitude and the geometric Pancharatnam) phase for ordinary and also generalized squeezed states are obtained. Applications of these general results to certain special cases of practical importance in the realm of quantum optics, such as two-photon interaction process, are briefly discussed.
Key words:  Boson Bogoliubov transformation, geometric phase, squeezed states

BOZONSKA BOGOLJUBOVLJEVA GRUPA I GENERALIZOVANA SAŽETA STANJA
Predložen je izbor proizvoljne faze Bogoljubovljevog unitarnog operatora koji obezbeđuje da skup svih homogenih Bogoljubovljevih transformacija bozonskih anihilacionih i kreacionih operatora čini kontinualnu neabelovu podrgupu SL(2,C) grupe. Ustanovljena su dva identiteta koja zadovoljava ovakav Bogoljubovljev operator i pomoću njih su nađeni izrazi za korelacionu amplitudu i geometrijsku (Pančaratnamovu) fazu generalizovanih sažetih stanja. Kratko je prodiskutovana primena ovih opštih rezultata na dvofotonske interakcione procese u kvantnoj optici.
Ključne reči: Bozonska Bogoljubovljeva transformacija, geometrijska faza, sažeta stanja