1	Stabilizing Carrier-Envelope Phase of KLS laser system Chengquan Li, Eric Moon, Zuoliang Duan, Jason Tackett ,Zenghu Chang April-05th-2006
2	CE Phase Stabilization Important for experiments utilizing identical few-cycle laser pulses CE Phase-dependent research Can use a stabilized frequency comb to perform spectroscopy. More applications to come!
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6	Frequency Comb and Laser Spectrum¹
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8	"The CE phase change can..." The CE phase change can be controlled by locking the offset frequency, f₀, to a known frequency. In the case of the KLS, f₀ is set equal to one-quarter of the repetition rate of the oscillator.
9	Experiment The KLS utilizes a Kerr-Lens Mode locked Ti:Sapphire oscillator emitting a ~77 million pulses per second. The pulses are roughly 12 fs at the output of the laser and carry nJ energy per pulse. The oscillator is the starting point for the self-referencing technique.
10	Phase locking loop
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12	CE Phase Stability After Pulse Amplification² A second f-2f interferometer after the KLS amplifier provides a means for quantifying the CE phase stabilization stability. 10% of the KLS amplifier output is sent to the experimental setup. White-light is generated in a sapphire plate and a BBO crystal provides second-harmonic generation.
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22	Slow feedback control wanted!! Using f-to-2f, the CE phase of oscillator can be locked over 3 hours; Fast dynamics founded in the CE phase drift in amplified laser pulses; Low frequency quasi-periodic CE phase drift in amplified laser pulses.
23	CE phase stabilization setup
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28	Summary Using f-to-2f interferometer, we stabilized the change of the carrier-envelope phase of the KLS over 3 hours. The CE phase drift was measured using a second f-to-2f interferometer. Under the slow feedback control, the Ce phase drift was suppressed into 100 mrad range for several minutes.
29	Thanks! Dr. Zenghu Chang Al Rankin KLS Members: Mahendra Shakya, Shambhu Ghimire, Chris Nakamura, and Steve Gilbertson Dr. Washburn and Dr. Corwin
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