Actually,
lasers with pulse duration widths in the fs/ps are quite usual for some applications.
One of recurring subjects in my line of work consists in the analysis of very short pulses (tens-hundreds of picoseconds) in rather deep logic (i.e. combinatorial gates in < 90nm microelectronic devices). Every new PhD student in this field immediately thinks about how wonderful an oscilloscope would be and why the previous researchers never considered this. It's quite a rite of passage, really.
There are some tricks that we've used for better results:
- test structures with various configurations but easy to capture logic output (1/0). A mathematical analysis of the captured events provides insightful data about the physical phenomenon
- test structures able to measure the duration of the logic event. Captured data can allow the computation of some parameters of the mathematical event model
- a fast analog memory that captures a few thousand points of the event with a fast (ps/tens of ps) sampling rate.
Usually, all these structures are on the chip itself, added during the design phase. This is not at all helpful for your stated application.
We have also experimented with building sensor chips that can be connected to the Device Under Test. While still useful, a lot of post-processing is required for getting back to the original physical event.
I realize that this discussion is not directly useful to you, but I wanted to make you aware about the inherent difficulty of directly observing the analog event. You may be more productive using some low-cost hardware tricks and software/mathematical analysis.
Maybe you can consider some signal conditioning/digitization circuitry or a series of voltage comparators to transform the pulse into logical events. Possibly a Logic Analyzer with adjustable-threshold inputs or a Pulse height analyzer or a Pulse Counter can be relevant to your application?
Cheers,
Dan