Femtosecond Pulse Delivery through Long Multimode Fiber Using Adaptive Pulse Synthesis

Itoh, Hiromi; Urakami, Takeo; Aoshima, Shin−ichiro; Tsuchiya, Yutaka

doi:10.1143/jjap.45.5761

Cited by 5 publications

(3 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recently, two-dimensional (2D) liquid crystal-based pulse shapers have been introduced 188 and employed in a number of experiments. 28,73,74,[189][190][191][192][193] These devices are capable of shaping the femtosecond laser pulse both in time and space, or in two spatial dimensions, allowing direct wavefront shaping. Furthermore, they can also be employed to shape several beams temporally.…”

Section: B Femtosecond Laser Pulse Shapingmentioning

confidence: 99%

Femtosecond quantum control of molecular dynamics in the condensed phase

Nuernberger

Vogt

Brixner

et al. 2007

Phys. Chem. Chem. Phys.

280

193

View full text Add to dashboard Cite

We review the progress in controlling quantum dynamical processes in the condensed phase with femtosecond laser pulses. Due to its high particle density the condensed phase has both high relevance and appeal for chemical synthesis. Thus, in recent years different methods have been developed to manipulate the dynamics of condensed-phase systems by changing one or multiple laser pulse parameters. Single-parameter control is often achieved by variation of the excitation pulse's wavelength, its linear chirp or its temporal subpulse separation in case of pulse sequences. Multiparameter control schemes are more flexible and provide a much larger parameter space for an optimal solution. This is realized in adaptive femtosecond quantum control, in which the optimal solution is iteratively obtained through the combination of an experimental feedback signal and an automated learning algorithm. Several experiments are presented that illustrate the different control concepts and highlight their broad applicability. These fascinating achievements show the continuous progress on the way towards the control of complex quantum reactions in the condensed phase.

show abstract

Section: B Femtosecond Laser Pulse Shapingmentioning

confidence: 99%

Femtosecond quantum control of molecular dynamics in the condensed phase

Nuernberger

Vogt

Brixner

et al. 2007

Phys. Chem. Chem. Phys.

280

193

View full text Add to dashboard Cite

show abstract

“…Contrary to the case of single mode fibers for which the spatial profile is maintained after propagation, the pattern emerging from a multimode fiber does not resemble the pattern launched at the input as explained before. Adaptive methods have been proposed to compensate for modal dispersion in telecommunications in order to deliver femtosecond pulses through multimode fibers but no simultaneous spatial control has been achieved [10,11].…”

Section: Introductionmentioning

confidence: 99%

Delivery of focused short pulses through a multimode fiber

Morales-Delgado¹,

Farahi²,

Papadopoulos³

et al. 2015

Opt. Express

104

View full text Add to dashboard Cite

Light propagation through multimode fibers suffers from spatial distortions that lead to a scrambled intensity profile. In previous work, the correction of such distortions using various wavefront control methods has been demonstrated in the continuous wave case. However, in the ultra-fast pulse regime, modal dispersion temporally broadens a pulse after propagation. Here, we present a method that compensates for spatial distortions and mitigates temporal broadening due to modal dispersion by a selective phase conjugation process in which only modes of similar group velocities are excited. The selectively excited modes are forced to follow certain paths through the multimode fiber and interfere constructively at the distal tip to form a focused spot with minimal temporal broadening. We demonstrate the delivery of focused 500 fs pulses through a 30 cm long step-index multimode fiber. The achieved pulse duration corresponds to approximately 1/30th of the duration obtained if modal dispersion was not controlled. Moreover, we measured a detailed two-dimensional map of the pulse duration at the output of the fiber and confirmed that the focused spot produces a twophoton absorption effect. This work opens new possibilities for ultra-thin multiphoton imaging through multimode fibers. References and links

show abstract

“…Dispersion [4][5][6] will broaden optical pulse, and cause serious limit on the transmission capacity and optical fiber bandwidth. For multimode fiber [7][8][9][10], mode dispersion plays a major role, this means different modes travel at different velocities to lead to the dispersion. For the single mode fiber [11][12][13][14][15], chromatic dispersion or intramodal dispersion is the main mechanism, and this is to say that the dispersion is caused by the different frequencies on different transmission speed.…”

Section: Introductionmentioning

confidence: 99%