Precision Spectroscopy of 130 Te 2 JAMES COKER

Precision Spectroscopy of 130 Te 2 JAMES COKER, J. E. FURNEAUX, AND NEIL SHAFER-RAY UNIVERSITY OF OKLAHOMA

Precision Spectroscopy of 130 Te 2 �Motivation

Precision Spectroscopy of 130 Te 2 �Motivation �Experimental Method spectroscopy cell optical cavity frequency x-axis

Precision Spectroscopy of 130 Te 2 �Motivation �Experimental Method spectroscopy cell optical cavity frequency x-axis � 130 Te 2 Properties basic our findings

Precision Spectroscopy of 130 Te 2 �Motivation �Experimental Method spectroscopy cell optical cavity frequency x-axis � 130 Te 2 Properties basic our findings �Coming soon…

Precision Spectroscopy of 130 Te 2 - Motivation

Precision Spectroscopy of 130 Te 2 - Motivation �Widely used as a frequency reference

Precision Spectroscopy of 130 Te 2 - Motivation �Widely used as a frequency reference �Large region documented, but features are buried about 18500 to 23800 cm-1

Precision Spectroscopy of 130 Te 2 - Motivation �Widely used as a frequency reference �Large region documented, but features are buried �Ground state well studied… J. Vergés et. al. , Physica Scripta, Vol. 25, 338 -350, (1982).

Precision Spectroscopy of 130 Te 2 - Motivation �Widely used as a frequency reference �Large region documented, but features are buried �Ground state well studied… but excited states not so much J. Vergés et. al. , Physica Scripta, Vol. 25, 338 -350, (1982).

Precision Spectroscopy of 130 Te 2 - Motivation �Widely used as a frequency reference �Large region documented, but features are buried �Ground state well studied… but excited states not so much �We have two goals with this work:

Precision Spectroscopy of 130 Te 2 - Motivation �Widely used as a frequency reference �Large region documented, but features are buried �Ground state well studied… but excited states not so much �We have two goals with this work: 1. to publish a few thousand frequency reference lines

Precision Spectroscopy of 130 Te 2 - Motivation �Widely used as a frequency reference �Large region documented, but features are buried �Ground state well studied… but excited states not so much �We have two goals with this work: 1. 2. to publish a few thousand frequency reference lines to measure the spec. constants of the exc. states to unprecedented precision

Precision Spectroscopy of 130 Te 2 – spectroscopy cell • Saturated Absorption

Precision Spectroscopy of 130 Te 2 – spectroscopy cell • Saturated Absorption • EM chopper

Precision Spectroscopy of 130 Te 2 – optical cavity • PZT fast feedback

Precision Spectroscopy of 130 Te 2 – optical cavity • PZT fast feedback • TEHC slow feedback

Precision Spectroscopy of 130 Te 2 – optical cavity • PZT fast feedback • TEHC slow feedback • modulate IR to make sidebands

Precision Spectroscopy of 130 Te 2 – optical cavity • • PZT fast feedback TEHC slow feedback modulate IR to make sidebands misaligned cavity and EOPM slightly ref: 2 d/λ=q+π-1(2 p+l+1)cos-1(1 -d/R)

Precision Spectroscopy of 130 Te 2 – frequency x-axis f(Vg) nonlinear, so we need a better f 0 and Δf V. Gerginov et. al. , Phys. Rev. A 73, 032504 (2006).

Precision Spectroscopy of 130 Te 2 – frequency x-axis f(Vg) nonlinear, so we need a better f 0 and Δf • know FSR to < 1/105 yielding <30 MHz uncertainty for entire 4 THz interval V. Gerginov et. al. , Phys. Rev. A 73, 032504 (2006).

Precision Spectroscopy of 130 Te 2 – frequency x-axis f(Vg) nonlinear, so we need a better f 0 and Δf • know FSR to < 1/105 yielding <30 MHz uncertainty for entire 4 THz interval • know f 0 from Cs IR transition to ~few k. Hz (5 p 66 s, 2 S, ½->5 p 66 p, 2 P 0, ½) found at 335208. 052259 GHz – thanks Haoquan Fan! V. Gerginov et. al. , Phys. Rev. A 73, 032504 (2006).

Precision Spectroscopy of 130 Te 2 – frequency x-axis both images show 18 redundant data sets

Precision Spectroscopy of 130 Te 2 – basic properties

Precision Spectroscopy of 130 Te 2 – basic properties J. Vergés et. al. , Physica Scripta, Vol. 25, 338 -350, 1982.

Precision Spectroscopy of 130 Te 2 – basic properties Our observed transitions span 22348. 7944 to 22582. 2892 cm-1 J. Vergés et. al. , Physica Scripta, Vol. 25, 338 -350, 1982.

Precision Spectroscopy of 130 Te 2 – basic properties Our observed transitions span 22348. 7944 to 22582. 2892 cm-1 • most of these are X 0 -B 0 transitions J. Vergés et. al. , Physica Scripta, Vol. 25, 338 -350, 1982.

Precision Spectroscopy of 130 Te 2 – basic properties Our observed transitions span 22348. 7944 to 22582. 2892 cm-1 • most of these are X 0 -B 0 transitions • being Σ-Σ, HL factors => no Q branches *cross-pol SAS would weaken them anyway J. Vergés et. al. , Physica Scripta, Vol. 25, 338 -350, 1982.

Precision Spectroscopy of 130 Te 2 – basic properties • about 20 overlapping vibrational bands (just R branches shown above)

Precision Spectroscopy of 130 Te 2 – basic properties • • about 20 overlapping vibrational bands (just R branches shown above) VERY HIGH line density (about 1 line per 2 GHz) right: just a small piece

Precision Spectroscopy of 130 Te 2 – basic properties • • • about 20 overlapping vibrational bands (just R branches shown above) VERY HIGH line density (about 1 line per 2 GHz) note that the Atlas had about 1 line per 12 GHz in this region

Precision Spectroscopy of 130 Te 2 – basic properties • • about 20 overlapping vibrational bands (just R branches shown above) VERY HIGH line density (about 1 line per 2 GHz) note that the Atlas had about 1 line per 12 GHz in this region we aim to accomplish two things: 1. publish a few thousand frequency reference lines 2. advance characterization of the excited states (spectroscopic constants)

Precision Spectroscopy of 130 Te 2 – our findings � After x-axes are set and lines are fit to Lorentzians, we have over 3000 reference lines with ~10 MHz uncertainty or better

Precision Spectroscopy of 130 Te 2 – our findings � After x-axes are set and lines are fit to Lorentzians, we have over 3000 reference lines with ~10 MHz uncertainty or better � The second task is much more difficult!

Precision Spectroscopy of 130 Te 2 – our findings � After x-axes are set and lines are fit to Lorentzians, we have over 3000 reference lines with ~10 MHz uncertainty or better � The second task is much more difficult! U(v, J) = Te + G(v) + B(v) J (J+1) – D(v) J 2 (J+1)2 + H(v) J 3 (J+1)3 This simplified Hamiltonian works well for 130 Te 2. The difficulty lies in the line density and the apparent ambiguity as to which line comes from which branch

Precision Spectroscopy of 130 Te 2 – our findings � After x-axes are set and lines are fit to Lorentzians, we have over 3000 reference lines with ~10 MHz uncertainty or better � The second task is much more difficult! U(v, J) = Te + G(v) + B(v) J (J+1) – D(v) J 2 (J+1)2 + H(v) J 3 (J+1)3 This simplified Hamiltonian works well for 130 Te 2. The difficulty lies in the line density and the apparent ambiguity as to which line comes from which branch matched 3 -7 and 5 -10 bands. Most lines to 1/108, the rest 1/107 this yields G, B, D, H for B 0 state v=7 and 10. Need more band origins!

Precision Spectroscopy of 130 Te 2 – coming soon • For some perspective, here’s the old data to scale with the size of all the data we now have.

Precision Spectroscopy of 130 Te 2 – coming soon • For some perspective, here’s the old data to scale with the size of all the data we now have. • After analysis we’ll have G, B, D and H in the B 0 state for v=2, …, 13

Precision Spectroscopy of 130 Te 2 – coming soon… After having measured G, B, D, and H we’ll have a good measure of these constants, allowing thorough characterization of the B 0 state.

Precision Spectroscopy of 130 Te 2 – coming soon… After having measured G, B, D, and H we’ll have a good measure of these constants, allowing thorough characterization of the B 0 state. We have also observed what appear to be Q branches. After we’ve assigned all the aforementioned bands of X 0 -B 0, it’s possible we can begin to characterize a Π or Δ state next. J. Vergés et. al. , Physica Scripta, Vol. 25, 338 -350, (1982).

Acknowledgements Neil Shafer-Ray, Professor, deceased James Coker Ph. D. student John Furneaux Professor James O’Doherty Undergraduate