Single-cycle pulse generation

Since I am working on characterization of single-cycle pulses, I was looking forward to this morning session on single cycle pulse generation. It was indeed exciting.

Günther Krauss (Germany) reported the synthesis of 4.3 fs pulses (1.9 optical cycle) centered on 1200 nm based on a two-branch Er:fiber laser system. Bruno Schmidt reported their CEP stable, single-cycle pulse compression in a hollow fiber followed by linear propagation through glass. They also generated 1.9 optical cycle pulses centered at 1800 nm. As I was wondering whether the single cycle pulse generated so far are all close to two cycles, he presented his newest result showing pulses with 9.5 fs, which is 1.6 optical cycles. The results are not published yet (in preparation); I calculated by hand how many cycles my pulses will be once the phases are adjusted flat. Guess what? 1.97 optical cycle ---still a single cycle. I can’t wait to go back to the lab and to measure my pulses.

Next, Friederike Junginger from Italy presented their REAL single cycle pulses in the Multi-THz range (4.6 fs, 22 THz, 1.0 cycle).

The most interesting talk I would say is the one about generating broadband blue pulses centered at 450 nm using sum frequency and difference frequency conversion presented by Haim Suchowski from Israel. He showed a very nice analogy between the SFG and the Bloch equation describing a two-level system. Through this analogy he is able to use adiabatic aperiodically poled KTP crystals to produce broadband, similar to the adiabatic population transfer. He has a nice movie showing the Bloch vector. Maybe I can get a copy from him then I will add it here.