1. Ultraslow Dissociation of H 2 + Via Intense Laser Pulses Presented by: Brad Moser And George Gibson DAMOP 2010

2. A Bound State - Our driving force is to control excitation of H 2 + - Population of the bound 3d  g state is a priority - Detectable via: - Vibrational signature in TOF - Molecular fluorescence - A two-color laser experiment presented itself: - 800 nm pulse to bond-soften - 400 nm pulse to resonantly excite to 3d  g - We found something new… DAMOP 2010

3. One-Color Floquet Model Bond-softening with 800 nm photon BS with 400 nm Laser pulse is 5x10 12 W/cm 2 DAMOP 2010

4. Two-Color Floquet Model Blue and Red pulses, each 5x10 12 W/cm 2, superposed in time and space. BS with 400 nm Emission of red photon creates an outer well. DAMOP 2010 Slow Dissociation

5. DAMOP 2010 TOF Spectra 1-Color Interactions - Graphs show H + ion signal vs ion momentum - Top graph: Experimental TOF data - Bottom graph: Numerical calculation

6. DAMOP 2010 TOF Spectra: 2-Color Interactions - Graphs show H + ion signal vs ion momentum - Red pulse held at 2x10 13 W/cm 2 - Blue pulse varied from 1 to 4 x10 13 W/cm 2 Ultraslow Dissociation

7. TOF Spectra 2-Color Interactions - Red pulse and Blue pulse are each 2x10 13 W/cm 2 - Effects: - 1  blue is shifted to Ultraslow Dissociation - Peak between 1  blue and 1  red is induced by outer well DAMOP 2010

8. 800 nm dissociation:800+400 nm dissociation:

9. Changing Potential Well Blue pulse has longer duration, therefore blue gap remains open while red effect drops out. DAMOP 2010

10. Conclusions -With 1  2  laser pulses, it is possible to produce ultraslow dissociation of hydrogen, the lightest molecule. -Such slow dissociation will allow us to probe the excited state structure of H 2 +. -We see evidence of time-dependent potential wells in the dissociate energy of the fragments. -For more details: Phys. Rev. A, Rapid Comm. 80, 041402(R) (2009) DAMOP 2010