1. Single-shot visualization of EVOLVING, light-speed index structures by multi-object phase contrast imaging
Zhengyan Li, Rafal Zgadzaj, Xiaoming Wang, Chih-Hao Pai, Yen-Yu Chang, Michael C. Downer
Department of Physics, University of Texas at Austin, Austin, TX 78712
Snapshots of Quasi-static Wakes
Movies of Evolving Wakes Captured in a Single Shot...
120 µm
0.4 ps
∆probe(r,)
aim of
this work
N. H. Matlis et al., Nature Phys. 2, 749 (2006) 1

2. The vacuum environment
35 cm interaction region?
1 deg. angle
L1 = ?
The vacuum environment
Optical quality window?
CCD1
CCD2
CCD3
CCD4
L0 = ?
800 nm, compressed 30 fs(?), < 1 mJ probe pulse, w0 < 1cm M1 M2
Lens f = 75 cm
OP1
OP2
OP3
OP4
What we want to do with index structure n(ζ,x,z)…
Multi-Object-Plane imaging, each object plane (OP) are imaged to different CCD.
Phase shift imprinted on probe at arbitrary z, not limited to OPs, is reconstructed.
In single shot, z-depending transverse profile at specific ζ is obtained.
With multi-shots, full visualization of index object n(ζ,x,z).
Questions:
Is the interaction length 35 cm, or longer?
Where is possible for us to couple laser into the chamber? What are the lengths of L0 and L1? To maintain a good imaging resolution, we hope L1 is not too large, what is the shortest length we can get?
Is there anything that potentially blocks or clips the beam between M1 and M2? Here the angle is 1 deg. = rad, so the inside diameter of the tube containing the laser has to be larger than 3 cm, if L0, L1 ~ 50 cm. Is it OK?

3. These are what we expected to observe with 6 cameras

4. Specs for MOPPCI in FACET
The minimum angle for oblique angle geometry
θmin = λ/πσ = deg @ σ = 100 um
0.72 deg @ σ = 20 um
Temporal walk-off
Δt = Lθ2/2c = 38 fs @ θ = 0.5 deg
152 fs @ θ = 1 deg
z-resolution for evolving bubble
δz = σ/θ = 5.73 mm @ σ = 100 um, θ = 1 deg
11.4 mm @ σ = 100 um, θ = 0.5 deg
2.29 mm @ σ = 20 um, θ = 0.5 deg
ζ-resolution and range for non-evolving bubble
δζ = max{σ(θ/2+φ)/c, tpr} = max{50, 30} = 50 fs
Δζ = Lθ(θ/2+φ)/c = 1.26 ps @ σ = 100 um, θ = 0.5 deg, φ = 8 deg