1. John T. Costello National Centre for Plasma Science & Technology (NCPST)/ School of Physical Sciences, Dublin City University www.physics.dcu.ie/~jtc (Very) Small Quantum Systems in Intense Bichromatic Fields -(and some thoughts on pump-probe) Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008

2. 2008 Membership- LIXAM (Orsay, France) D. Cubaynes, D Glijer, M. Meyer DESY (Hamburg, Germany) S. Düsterer, H. Redlin, W-B Li, J. Feldhaus Dublin City University (Ireland) J. Dardis, P. Hayden, P. Hough, E. T. Kennedy, V. Richardson and J. T. Costello Formerly QUB. C. Lewis et al. Two-Colour ‘FLASH’ Collaboration Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008 Photoionization Experiments with the Ultrafast EUV Laser FLASH - Free Electron Laser in Hamburg J T Costello, J Phys Conf Ser 88 Art No 012057 (2007)

3. Small does not mean simple (especially in intense fields) Two colour laser experiments on SQS very much in vogue in the 1970s & 1980s So what’s new (possible) with FLASH - (LCLS) - XFEL ? What do we need from the FEL and the ‘synchronised’ optical laser(s) ? Train of thought………. Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008

4. SQS in Intense Fields Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008 Corkum P B and Krausz F, Attosecond Science Nature Physics 3 381 (2007) In vogue NOW ! ‘Knight Doublet’ P L Knight, J. Phys. B: AMP 11 L 511 (1978) In vogue THEN !

5. Atoms (Molecules) in Intense XUV + NIR Fields Coherent photoionization processes in superposed fields Optically probing fragments in XUV dissociated H 2 Next steps - Two Colour Resonant Processes Technological Developments for Next Phase Bichromatic Laser Field-SQS Experiments SQS in Bichromatic Fields Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008 M Meyer yesterday - FOCUS ON

6. Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008 SQS in Bichromatic Fields Proposal 1 - Quantum Optics with Unbound States Loh, Greene & Leone Chem. Phys 350 7 (2008) EIT & coherent population transfer (CPT) - optical switching, slow light (storage) etc. Probe Pump LICS Coherent Population Transfer with Autoionising States (AIS) Karapanagioti et al. PRL 74 2431 (1995)

7. Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008 SQS in Bichromatic Fields Proposal 1 - Quantum Optics with Unbound States Loh, Greene & Leone Chem. Phys 350 7 (2008) First? demonstartion of EUV transparency switching Karapanagioti et al. PRL 74 2431 (1995) Autler-Townes with AIS !

8. Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008 SQS in Bichromatic Fields Proposal 1 - Quantum Optics with Unbound States Conventional lasers: QO with valence electron - continuum probes FLASH: QO with sub-valence electron - continuum probes (e.g., Meyer Kr, 3d 10 - 3d 9 4d proposal) XFEL: QO with core electron - continuum probes (e.g., Duesterer et al., LCLS - Ne, 1s 2 - 1snp proposal) Summary: EIT & CPT with X-rays and autoionising states

9. Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008 SQS in Bichromatic Fields Proposal 1 - Quantum Optics with Unbound States (X)FEL: Wavelength tunable and well characterised (shot to shot) - wavelength, bandwidth, spectral dist., energy, etc. Optical laser(s): Ideally two or more tunable OPAs with 5+ picosecond duration (to overcome 0.5 ps jitter problem). For sidebands must be UV laser (h >4 eV) as BW of LCLS & XFEL will be 0.2% (4eV at 2 KeV) Detectors: We want everything [Ions, electrons, photons (IR - XUV), spin and polarisation (Stokes parameters) and all in co-incidence for ‘complete experiments’ - A. Wolf question Summary: EIT & CPT with X-rays and autoionising states Note: Not to forget Moshammer and Quantum-Zeno Effect (if field is intense)

10. Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008 SQS in Bichromatic Fields Proposal 1 - Quantum Optics with Unbound States (X)FEL: Wavelength tunable and well characterised (shot to shot) - wavelength, bandwidth, spectral dist., energy, etc. Optical laser(s): Ideally two or more tunable OPAs with 5+ picosecond duration (to overcome 0.5 ps jitter problem). For sidebands must be UV laser (h >4 eV) as BW of LCLS & XFEL will be 0.2% (4eV at 2 KeV) Detectors: We want everything [Ions, electrons, photons (IR - XUV), spin and polarisation (Stokes parameters) and all in co-incidence for ‘complete experiments’ - A. Wolf question Summary: EIT & CPT with X-rays and autoionising states Note: Not to forget Moshammer and Quantum-Zeno Effect (if field is intense)

11. Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008 SQS in Bichromatic Fields Proposal 2 - Post collision probes of simple molecules

12. M Meyer et al. PRA 74 011401R (2006) P Radcliffe, et al., APL 90 131108 (2007) Jitter - Problem for probing prompt dissociation dynamics…… ~500 fs New ultrafast EUV-modulated optical-reflectivity methods: 1.C. Gahl et al., Nature Photonics 2 165-169 (2008) 2.T. Maltezopoulos et al., New J Phys 10 Art. No. 033026 (2008) SQS in Bichromatic Fields Primary phase - better to use XUV- XUV Pump-Probe Setup proposed by Moshammer-Vrakking. Sub-fs resolution…………. Evolution of Atomic Fragments - Here we can use pump-probe with OPAs synchronised to (X)FEL (ps) And fluorescence with ICCD spectroscopy for bound states (ns)

13. Further Steps for AMOP at FELs - Solutions to the timing jitter problem ? Nature Physics March 2008 Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008

14. Even Further Steps for AMOP at XFEL - Attosecond Pulses ? Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008

15. R P Madden and K Codling PRL 10 516-518 (1963) ‘New Knobs’ FEL Frequency FEL Intensity Tunable (X)FEL - Driving autoionising transitions in intense XUV fields Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008

16. Next Phase (FLASH to XFEL) 1.To date we have looked only at one and two colour non- resonant photoionization processes 2.FEL tunable and so we can explore resonant two colour processes where inner shell electrons dominate - QO in the XUV/X-ray with AIS…….. 3.Study fragmentation and ionization from vibrationally excited/selected wavepackets in simple molecules 4.Beyond 2010: Seeding, fs jitter and attosecond pulses (XFEL): Photoionization - Dissociation Imaging Dynamics Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008

17. New ‘Plasma-SQS’ Targets ? Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008 New targets - Colliding Plasmas ? Atomic Ca/Ca + - Emission Imaging @ 423 nm Laser Pulse Energy: 10 -150 mJ/ beam Laser Pulse duration: 12 - 15 ns Focal Spot Size:~ 100  m Irradiance: 10 10 - 10 11 W.cm -2 Warm (Moderately) Dense Matter H Luna, K D Kavanagh & J T Costello, J Appl Phys 101, Art No 033302 (2007)

18. For Pump-Probe at FLASH - XFEL Small Quantum Systems Workshop, Aarhus, Oct 28 - 30, 2008 1.Please, please, please include multiple OPA beamlines with fs - ps variable pulse duration and UV - FIR tunability 2.Optical tunability can compensate for the fact that FELs are often locked on ‘sweet spot’ wavelengths. 3.We want everything [ions, electrons, photons (IR - XUV), spin and polarisation (Stokes parameters) and all in co- incidence for ‘complete experiments’] - A. Wolf again….. 4.FEL diagnostics, diagnostics, diagnostics,…….. 5.State of the art (but reliable) optical laser sources/ diagnostics at the XFEL => XFEL development phase OK !