1. Bubble Acceleration with few-cycle pulses
Max-Planck-Institut
für Quantenoptik
Bubble Acceleration with few-cycle pulses
Michael Geissler, Jörg Schreiber, Florian Grüner
and Jürgen Meyer-ter-Vehn

2. Outline 3D-PIC Simulations of: few cycle pulses: Scaling
Density Profile
Closer look on “bubble-electrons”
Experiments (Rutherford, Jena, MPQ…)

3. Numerical Tool 3D-PIC Code for Ideal Laser Matter Interaction:
ILLUMINATION
x – Laser Polarization
z – Propagation direction y
Laser Pulse

4. 5fs, a=5, w0=5µm, p=8µm

5. 5fs, a=5

6. 5fs, a=5, 70MeV e-

7. 5fs, a=5, 60-80MeV e-

8. 5fs, a=5, 60-80MeV e-

9. 5fs, a=5, 60-80MeV e-

10. 5fs, w0=5µm, p=8µm
a=3
a=5
a=10
a=30

11. 5fs Summary a=3 a=5 a=10 a=30 Epeak (80MeV) 80MeV 130MeV 310MeV Lmax
Ezmax
0.5TV/m
1.1TV/m
1.6TV/m
2.3TV/m
ne,peak Etot,peak
1.2x109
14mJ
3.8x109
75mJ
24x109
1300mJ

12. 5fs Scaling

13. with Gas denstity profile:
5fs, a=5
with Gas denstity profile:
Focus position N0 z
200µm
200µm

14. 5fs, a=5, p=8µm, profile

15. MPQ: 5fs, a=5, w0=2µm; 20mJ

16. RAL: 40fs, a=0.767, 390mJ

17. RAL: 40fs, a=0.767, 390mJ Ne [10201/cm³] Intensity [1019 W/cm²] z [µm]
Ez [1012V/m]
z [µm]

18. Jena: 80fs, a=3

19. 80fs, a=3
Ne [10201/cm³]
I [1019W/cm²]

20. Conclusions Few-cycle pulses are most efficent for bubble acceleration
(longer pulses become few-cycle during propagation)
Acceleration is limited due:
Rb=w0*a0.25 ~Eacc
Short lifetime of the bubble (~ µm)
Precise control of gas density and length is necessary
Multistages:
Use a small amount (20-100mJ) in the first stage, but what afterwards?
Wakefield? second bubble? How to inject the electron?

21. 40fs, a=3