Temperature Feedback Control for Long-Term Carrier-Envelope Phase Locking
Reference Number: 09-11
Inventors: Zenghu Chang, Chenxia Yun, Shouyuan Chen, He Wang, and Michael Chini
For reliable applications of the carrier-envelope phase (CEP) stabilized pulses, low
phase noise and excellent long-term stability are crucial. Researchers in the J.R.
Macdonald Laboratory at Kansas State University have discovered and demonstrated a
patent-pending method for greatly extending the typical stabilization time of the
oscillator. Without adding new optical elements or disturbing the operation of the
oscillator, this scheme is compact, easy to operate, and economical. The researchers
have achieved CEP stabilization lasting for 12 hours on a daily basis and more than
34 hours on occasion, which is 3-4 times longer than the typical locking time without
temperature feedback control.
The long-term CEP lock is required in the single attosecond experiments since such
experiments usually take many hours to collect sufficient counts to suppress the statistical
noise. It is common practice to obtain CEP stable pulses from the oscillator by locking
the carrier-envelope offset frequency (fCEO ) through modulating the pump power with
an acousto-optic modulator (AOM). Due to the change of environmental conditions in
laser laboratories, fCEO may drift out of AOM locking range, which limits fCEO stabilization
time. The K-State research team demonstrated a temperature feedback scheme to compensate
the slow fCEO drift and extend the CEP stabilization duration.
- Extending oscillator CEP stabilization by 3-4X
- No additional optical elements
Fig. 1. (a) 34 hours CEP stabilization achieved by employing the double feedback loop;
the blue curve shows the AOM driving voltage output; the pink curve shows the temperature
of the crystal; (b) Error signal from locking electronics.
- Frequency metrology
- Attosecond physics
- Coherent control experiments with CEP stabilized few cycle pulses
- High harmonic generation using oscillator beam
- U.S. patent #8,228,961 issued on July 24, 2012.
Kansas State University Research Foundation seeks to have discussions with companies
that are interested in licensing and/or research collaborations.
Interested parties should contact:
Kansas State University Institute for Commercialization (KSU-IC)
2005 Research Park Circle Manhattan, KS 66502
Tel: 785-532-3900 Fax: 785-532-3909