Abstract book - Prof. Per Jensen, Ph.D. - Bergische Universität ...

120 Poster session, H7Laser-Induced Far-Infrared Stimulated Emission fromthe High Rydberg States of Nitric OxideH. Furukawa, K. Abe, M. Araki, and K. TsukiyamaGraduate School of Chemical Sciences and Technology, Tokyo University of Science,Japan, jb111708@ed.tus.ac.jpFurukawa H.Abe K.Araki M.Tsukiyama K.Laser-induced far-infrared stimulated emissions from the 9sσ ~ 14sσ, 8f ~ 14f and12pσπ ~ 14pσπ Rydberg states, having predissociation and/or autoionization, throughthe 3sσ A 2 Σ + state of Nitric Oxide (NO) were observed by using the optical-opticaldouble resonance excitation technique.The emissions around 69, 52 and 38 µm from the 12f (υ = 0) state were observed in thedispersed emission spectrum as shown in Fig.1 and were identified as the 12f → 11g →10f → 9g(0,0,0,0) cascade transitions. The observed emissions were not four-wavemixing but the stimulated emissions.The emissions around 40 and 60 µm for the 9sσ → 8pσ(0,0) and 10sσ → 9pσ(0,0)transitions were observed by the excitation at the predissociative 9sσ(υ = 0) and10sσ(υ = 0) Rydberg states, respectively. The emissions from the 8f and 9f states werealso observed by the excitations at the same states. The 8f ← 9sσ(0,0) and 9f ←10sσ(0,0) excitations, i.e. the (n-1)f ← nsσ excitation channels, by the sσ ↔ dσ mixingcould be expected. The analogous emissions and excitations in υ = 1 were produced bythe excitations at the autoionization Rydberg states.Since the emissions were observed in far-infrared and were obtained by the (n-1)f ←nsσ excitations, a type of the present emissions can be the stimulated emission inducedby a black-body radiation at a room temperature and the (n-1)f ← nsσ excitations can beproduced by absorption of the black-body radiation [1].12f → 11g(0,0)FIR Intensity(arb. unit)10f → 9g(0,0)11g → 10f(0,0)35 40 45 50 55 60 65 70 75 80FIR Emission Wavelengtn(µm)Fig. 1: The dispersed far-infrared emission from the 12f (υ = 0) Rydberg state. Theobserved three peaks were identified as the 12f → 11g → 10f → 9g cascade transitions.Reference[1] T. F. Gallagher, Rydberg Atoms, Cambridge Univercity Press, 1994