Untersuchungen uber die anomale Dispersion angeregter Gase (Ladenburg, pp.15–25) AND Untersuchungen über die anomale Dispersion angeregter Gase II Teil. Anomale Dispersion in angeregtem Neon Einfluß von Strom und Druck, Bildung und Vernichtung angeregter Atome (Kopfermann & Ladenburg, pp. 26-50) AND Untersuchungen uber die anomale Dispersion angeregter Gase III. Teil. Ubergangswahrscheinlichkeit und Dichte angeregter Atome im Neon; statistisches Gleichgewicht in der positiven Saule" (Kopfermann & Ladenburg, pp. 51-61) in Zeitschrift fur Physik 48, 1928. WITH Untersuchungen uber die anomale Dispersion angeregter Gase V. Teil: Negative Dispersion in angeregtem Neon (Kopfermann & Ladenburg pp. 167–188) in Zeitschrift fur Physik 65, 1930 [2 VOLUMES 1st EVIDENCE STIMULATED EMISSION]

Berlin: Julius Springer. 1st Edition. TWO VOLUME FIRST EDITIONS OF A SERIES OF PAPERS “IN WHICH [KOPFERMANN AND LADENBURG] PRESENTED THE FIRST EVIDENCE OF ‘NEGATIVE DISPERSION,’ WHAT PHYSICISTS NOW CALL STIMULATED EMISSION” (James, 100 Years at the Intersection of Chemistry and Physics, 86). “Some historians of science have even argued that with just a bit more luck Ladenburg and Kopfermann might have observed the first laser pulse” (James, 86). That might seem hyperbole. It isn’t.

To understand just how close the work in the papers offered here brought Ladenburg and Kopfermann: “One of the most important concepts necessary in understanding laser operation is the fact that quantization of energy in the atom results in discrete energy levels. In addition, transitions from one energy level to another must be possible in order for light emission to occur, and these transitions include both spontaneous and stimulated emission” (Parry-Hill et al, Spontaneous and Stimulated Process). The Ladenburg and Kopfermann papers offered here present the first definitive evidence of one of the required transitions: stimulated emissions.

Further, dispersion in electrically excited neon “played a central role in the development of quantum theory in general” (James, 85). In earlier work, Ladenburg made “important contributions to the transformation of classical dispersion into its quantum counterpart… [taking] the “first correct step towards the formulation of the quantum mechanical interpretation of dispersion [and had come] very close to discovering amplification by stimulated emission" (James, 85; Bertolotti, Masers and Lasers, 15).

In the papers offered here, Kopfermann and Ladenburg continue and build upon Ladenburg’s earlier work and are able to present a “demonstration of negative dispersion in a neon gas discharge tube as evidence of stimulated light emission… a prerequisite for the development of laser emission detected much later” (Fritz-Haber-Institut, Historical Review). Item #1561

CONDITION & DETAILS: Berlin: Julius Springer. Two Volumes. Vol. 48, 891pp., Vol. 65, 876pp. NOT ex-library. Solidly and cleanly bound in blue cloth, gilt-lettered at the spine. As is typical of German volumes of this era, minor age toning within; some old creasing. Very good + condition.

Price: $275.00